emissions of air pollutants, annual growth rate in Taiwan
Taiwan: emissions of air pollutants, annual growth rate was -3.74 % change on previous year in 2022. ◆ Volatile
Latest (2022)
-3.74 % change on previous year
Change on year
down 55.8%
World rank
205th
of 219 countries
All-time high
21.65 % change on previous year
in 1978
All-time low
-18.1 % change on previous year
in 2013
Years of data
272
1751–2022
emissions of air pollutants, annual growth rate in Taiwan, 1751–2022
Source: Statizoid (derived). Measured in % change on previous year.
Analysis
Taiwan recorded -3.74 % change on previous year for emissions of air pollutants, annual growth rate in 2022.
The figure is down 55.8% on the previous year and up 77.7% over ten years.
Over the whole period, emissions of air pollutants, annual growth rate in Taiwan peaked at 21.65 % change on previous year in 1978 and was at its lowest, -18.1 % change on previous year, in 2013.
Taiwan ranks 205th of 219 countries on this measure, in the bottom quarter.
The series is highly variable year to year, so single readings are best treated with caution.
emissions of air pollutants, annual growth rate in Taiwan, year by year
| Year | % change on previous year | Change |
|---|---|---|
| 1751 | 0.1697 % change on previous year | — |
| 1752 | 0.1694 % change on previous year | -0.2% |
| 1753 | 0.1689 % change on previous year | -0.3% |
| 1754 | 0.1686 % change on previous year | -0.2% |
| 1755 | 0.1683 % change on previous year | -0.2% |
| 1756 | 0.1676 % change on previous year | -0.5% |
| 1757 | 0.1673 % change on previous year | -0.2% |
| 1758 | 0.167 % change on previous year | -0.2% |
| 1759 | 0.1665 % change on previous year | -0.3% |
| 1760 | 0.166 % change on previous year | -0.3% |
| 1761 | 0.1664 % change on previous year | +0.3% |
| 1762 | 0.1661 % change on previous year | -0.2% |
| 1763 | 0.1656 % change on previous year | -0.3% |
| 1764 | 0.1651 % change on previous year | -0.3% |
| 1765 | 0.1648 % change on previous year | -0.2% |
| 1766 | 0.1643 % change on previous year | -0.3% |
| 1767 | 0.1638 % change on previous year | -0.3% |
| 1768 | 0.1636 % change on previous year | -0.2% |
| 1769 | 0.1631 % change on previous year | -0.3% |
| 1770 | 0.1626 % change on previous year | -0.3% |
| 1771 | 0.1628 % change on previous year | +0.1% |
| 1772 | 0.1623 % change on previous year | -0.3% |
| 1773 | 0.162 % change on previous year | -0.2% |
| 1774 | 0.1615 % change on previous year | -0.3% |
| 1775 | 0.161 % change on previous year | -0.3% |
| 1776 | 0.1605 % change on previous year | -0.3% |
| 1777 | 0.16 % change on previous year | -0.3% |
| 1778 | 0.1598 % change on previous year | -0.2% |
| 1779 | 0.1593 % change on previous year | -0.3% |
| 1780 | 0.159 % change on previous year | -0.2% |
| 1781 | 0.1586 % change on previous year | -0.3% |
| 1782 | 0.1581 % change on previous year | -0.3% |
| 1783 | 0.1578 % change on previous year | -0.2% |
| 1784 | 0.1573 % change on previous year | -0.3% |
| 1785 | 0.1569 % change on previous year | -0.3% |
| 1786 | 0.1564 % change on previous year | -0.3% |
| 1787 | 0.1561 % change on previous year | -0.2% |
| 1788 | 0.1554 % change on previous year | -0.4% |
| 1789 | 0.1552 % change on previous year | -0.2% |
| 1790 | 0.1547 % change on previous year | -0.3% |
| 1791 | 0.154 % change on previous year | -0.4% |
| 1792 | 0.1536 % change on previous year | -0.3% |
| 1793 | 0.1533 % change on previous year | -0.2% |
| 1794 | 0.1527 % change on previous year | -0.4% |
| 1795 | 0.1522 % change on previous year | -0.3% |
| 1796 | 0.152 % change on previous year | -0.2% |
| 1797 | 0.1515 % change on previous year | -0.3% |
| 1798 | 0.1508 % change on previous year | -0.4% |
| 1799 | 0.1506 % change on previous year | -0.2% |
| 1800 | 0.1501 % change on previous year | -0.3% |
| 1801 | 0.149 % change on previous year | -0.7% |
| 1802 | 0.1486 % change on previous year | -0.3% |
| 1803 | 0.1481 % change on previous year | -0.3% |
| 1804 | 0.1477 % change on previous year | -0.3% |
| 1805 | 0.1473 % change on previous year | -0.3% |
| 1806 | 0.1468 % change on previous year | -0.3% |
| 1807 | 0.1464 % change on previous year | -0.3% |
| 1808 | 0.1459 % change on previous year | -0.3% |
| 1809 | 0.1455 % change on previous year | -0.3% |
| 1810 | 0.1451 % change on previous year | -0.3% |
| 1811 | 0.1433 % change on previous year | -1.2% |
| 1812 | 0.1431 % change on previous year | -0.1% |
| 1813 | 0.1425 % change on previous year | -0.5% |
| 1814 | 0.142 % change on previous year | -0.3% |
| 1815 | 0.1416 % change on previous year | -0.3% |
| 1816 | 0.1412 % change on previous year | -0.3% |
| 1817 | 0.1408 % change on previous year | -0.3% |
| 1818 | 0.1404 % change on previous year | -0.3% |
| 1819 | 0.1399 % change on previous year | -0.3% |
| 1820 | 0.1393 % change on previous year | -0.5% |
| 1821 | 0.212 % change on previous year | +52.1% |
| 1822 | 0.2113 % change on previous year | -0.3% |
| 1823 | 0.2104 % change on previous year | -0.4% |
| 1824 | 0.2095 % change on previous year | -0.4% |
| 1825 | 0.2087 % change on previous year | -0.4% |
| 1826 | 0.208 % change on previous year | -0.3% |
| 1827 | 0.2071 % change on previous year | -0.4% |
| 1828 | 0.2065 % change on previous year | -0.3% |
| 1829 | 0.2054 % change on previous year | -0.5% |
| 1830 | 0.2048 % change on previous year | -0.3% |
| 1831 | 0.271 % change on previous year | +32.3% |
| 1832 | 0.2699 % change on previous year | -0.4% |
| 1833 | 0.2685 % change on previous year | -0.5% |
| 1834 | 0.2673 % change on previous year | -0.4% |
| 1835 | 0.2662 % change on previous year | -0.4% |
| 1836 | 0.2649 % change on previous year | -0.5% |
| 1837 | 0.2638 % change on previous year | -0.4% |
| 1838 | 0.2626 % change on previous year | -0.4% |
| 1839 | 0.2613 % change on previous year | -0.5% |
| 1840 | 0.26 % change on previous year | -0.5% |
| 1841 | 0.2635 % change on previous year | +1.3% |
| 1842 | 0.2622 % change on previous year | -0.5% |
| 1843 | 0.2609 % change on previous year | -0.5% |
| 1844 | 0.2596 % change on previous year | -0.5% |
| 1845 | 0.2585 % change on previous year | -0.4% |
| 1846 | 0.2572 % change on previous year | -0.5% |
| 1847 | 0.2562 % change on previous year | -0.4% |
| 1848 | 0.2549 % change on previous year | -0.5% |
| 1849 | 0.2536 % change on previous year | -0.5% |
| 1850 | 0.2524 % change on previous year | -0.5% |
| 1851 | 0.259 % change on previous year | +2.6% |
| 1852 | 0.265 % change on previous year | +2.3% |
| 1853 | 0.2716 % change on previous year | +2.5% |
| 1854 | 0.2781 % change on previous year | +2.4% |
| 1855 | 0.2849 % change on previous year | +2.5% |
| 1856 | 0.2915 % change on previous year | +2.3% |
| 1857 | 0.2985 % change on previous year | +2.4% |
| 1858 | 0.3055 % change on previous year | +2.4% |
| 1859 | 0.3129 % change on previous year | +2.4% |
| 1860 | 0.3204 % change on previous year | +2.4% |
| 1861 | 0.266 % change on previous year | -17.0% |
| 1862 | 0.2677 % change on previous year | +0.6% |
| 1863 | 0.2693 % change on previous year | +0.6% |
| 1864 | 0.2708 % change on previous year | +0.5% |
| 1865 | 0.2724 % change on previous year | +0.6% |
| 1866 | 0.2742 % change on previous year | +0.7% |
| 1867 | 0.2755 % change on previous year | +0.5% |
| 1868 | 0.2775 % change on previous year | +0.7% |
| 1869 | 0.2792 % change on previous year | +0.6% |
| 1870 | 0.2807 % change on previous year | +0.5% |
| 1871 | 0.2794 % change on previous year | -0.5% |
| 1872 | 0.2786 % change on previous year | -0.3% |
| 1873 | 0.2784 % change on previous year | -0.1% |
| 1874 | 0.278 % change on previous year | -0.1% |
| 1875 | 0.2776 % change on previous year | -0.1% |
| 1876 | 0.2772 % change on previous year | -0.1% |
| 1877 | 0.2768 % change on previous year | -0.1% |
| 1878 | 0.2766 % change on previous year | -0.1% |
| 1879 | 0.2763 % change on previous year | -0.1% |
| 1880 | 0.268 % change on previous year | -3.0% |
| 1881 | 0.2544 % change on previous year | -5.1% |
| 1882 | 0.2544 % change on previous year | -0.0% |
| 1883 | 0.2546 % change on previous year | +0.1% |
| 1884 | 0.2545 % change on previous year | -0.0% |
| 1885 | 0.2548 % change on previous year | +0.1% |
| 1886 | 0.2549 % change on previous year | +0.0% |
| 1887 | 0.2546 % change on previous year | -0.1% |
| 1888 | 0.2551 % change on previous year | +0.2% |
| 1889 | 0.2552 % change on previous year | +0.0% |
| 1890 | 0.2551 % change on previous year | -0.0% |
| 1891 | 1.37 % change on previous year | +437.2% |
| 1892 | 1.35 % change on previous year | -1.2% |
| 1893 | 1.34 % change on previous year | -1.2% |
| 1894 | 1.32 % change on previous year | -1.2% |
| 1895 | 1.31 % change on previous year | -1.2% |
| 1896 | 1.3 % change on previous year | -0.7% |
| 1897 | 1.51 % change on previous year | +16.5% |
| 1898 | 1.57 % change on previous year | +3.6% |
| 1899 | 1.06 % change on previous year | -32.3% |
| 1900 | 5.36 % change on previous year | +405.9% |
| 1901 | 3.3 % change on previous year | -38.5% |
| 1902 | 4.7 % change on previous year | +42.6% |
| 1903 | 2.04 % change on previous year | -56.7% |
| 1904 | 2.94 % change on previous year | +44.3% |
| 1905 | 4.16 % change on previous year | +41.7% |
| 1906 | 2.74 % change on previous year | -34.2% |
| 1907 | 4.33 % change on previous year | +58.3% |
| 1908 | 2.37 % change on previous year | -45.4% |
| 1909 | 2.3 % change on previous year | -2.9% |
| 1910 | 2.36 % change on previous year | +2.8% |
| 1911 | 0.7037 % change on previous year | -70.2% |
| 1912 | 0.5352 % change on previous year | -23.9% |
| 1913 | 1.05 % change on previous year | +95.9% |
| 1914 | 0.2433 % change on previous year | -76.8% |
| 1915 | 0.4181 % change on previous year | +71.8% |
| 1916 | 1.54 % change on previous year | +268.3% |
| 1917 | 1.23 % change on previous year | -20.4% |
| 1918 | 0.0156 % change on previous year | -98.7% |
| 1919 | 2.1 % change on previous year | +13350.9% |
| 1920 | -2.45 % change on previous year | -216.6% |
| 1921 | 1.93 % change on previous year | -178.9% |
| 1922 | 7.76 % change on previous year | +301.8% |
| 1923 | 4.35 % change on previous year | -43.9% |
| 1924 | 3.58 % change on previous year | -17.7% |
| 1925 | 4.88 % change on previous year | +36.3% |
| 1926 | 3.71 % change on previous year | -24.1% |
| 1927 | 2.86 % change on previous year | -22.9% |
| 1928 | -1.59 % change on previous year | -155.8% |
| 1929 | 1.06 % change on previous year | -166.3% |
| 1930 | 2.45 % change on previous year | +131.6% |
| 1931 | -0.4548 % change on previous year | -118.6% |
| 1932 | 0.8266 % change on previous year | -281.8% |
| 1933 | 4.03 % change on previous year | +387.3% |
| 1934 | 1.27 % change on previous year | -68.5% |
| 1935 | 2.35 % change on previous year | +85.0% |
| 1936 | 1.43 % change on previous year | -39.3% |
| 1937 | 2.54 % change on previous year | +77.9% |
| 1938 | 2.01 % change on previous year | -20.8% |
| 1939 | 3.85 % change on previous year | +91.8% |
| 1940 | 1.36 % change on previous year | -64.7% |
| 1941 | 8.58 % change on previous year | +531.5% |
| 1942 | 0.1399 % change on previous year | -98.4% |
| 1943 | 6.42 % change on previous year | +4485.4% |
| 1944 | -4.17 % change on previous year | -165.0% |
| 1945 | -9.9 % change on previous year | +137.4% |
| 1946 | 6.75 % change on previous year | -168.2% |
| 1947 | 5.86 % change on previous year | -13.2% |
| 1948 | 5.83 % change on previous year | -0.6% |
| 1949 | 0.4852 % change on previous year | -91.7% |
| 1950 | 9.27 % change on previous year | +1810.2% |
| 1951 | 10.2 % change on previous year | +10.0% |
| 1952 | -1.26 % change on previous year | -112.3% |
| 1953 | 0.7931 % change on previous year | -163.1% |
| 1954 | 2.96 % change on previous year | +272.8% |
| 1955 | -5.02 % change on previous year | -269.8% |
| 1956 | 1.96 % change on previous year | -139.0% |
| 1957 | -6.14 % change on previous year | -414.1% |
| 1958 | 2.87 % change on previous year | -146.8% |
| 1959 | 0.0556 % change on previous year | -98.1% |
| 1960 | -6.36 % change on previous year | -11547.9% |
| 1961 | -6.52 % change on previous year | +2.5% |
| 1962 | -3.34 % change on previous year | -48.7% |
| 1963 | -6.3 % change on previous year | +88.7% |
| 1964 | -3.59 % change on previous year | -43.1% |
| 1965 | 2.19 % change on previous year | -161.1% |
| 1966 | 11.18 % change on previous year | +409.9% |
| 1967 | 13.42 % change on previous year | +20.1% |
| 1968 | 6.13 % change on previous year | -54.3% |
| 1969 | 10.16 % change on previous year | +65.8% |
| 1970 | 9.97 % change on previous year | -1.9% |
| 1971 | 2.98 % change on previous year | -70.1% |
| 1972 | 15.48 % change on previous year | +419.3% |
| 1973 | 21.52 % change on previous year | +39.0% |
| 1974 | 5.83 % change on previous year | -72.9% |
| 1975 | 12.25 % change on previous year | +110.0% |
| 1976 | 13.69 % change on previous year | +11.7% |
| 1977 | 12.4 % change on previous year | -9.4% |
| 1978 | 21.65 % change on previous year | +74.5% |
| 1979 | 13.82 % change on previous year | -36.2% |
| 1980 | 4.42 % change on previous year | -68.0% |
| 1981 | 13.21 % change on previous year | +198.9% |
| 1982 | 14.16 % change on previous year | +7.2% |
| 1983 | 10.82 % change on previous year | -23.6% |
| 1984 | 7.68 % change on previous year | -29.0% |
| 1985 | 7.06 % change on previous year | -8.1% |
| 1986 | 5.15 % change on previous year | -27.0% |
| 1987 | 4.53 % change on previous year | -12.1% |
| 1988 | 6.46 % change on previous year | +42.5% |
| 1989 | 4.83 % change on previous year | -25.3% |
| 1990 | 3.25 % change on previous year | -32.7% |
| 1991 | 4.81 % change on previous year | +48.2% |
| 1992 | 6 % change on previous year | +24.6% |
| 1993 | 5.19 % change on previous year | -13.4% |
| 1994 | 3.99 % change on previous year | -23.1% |
| 1995 | -2.21 % change on previous year | -155.2% |
| 1996 | -0.8 % change on previous year | -63.7% |
| 1997 | 0.336 % change on previous year | -142.0% |
| 1998 | -3.96 % change on previous year | -1278.5% |
| 1999 | -3.98 % change on previous year | +0.5% |
| 2000 | 0.3087 % change on previous year | -107.8% |
| 2001 | -6.41 % change on previous year | -2178.3% |
| 2002 | -6.46 % change on previous year | +0.7% |
| 2003 | -5.26 % change on previous year | -18.6% |
| 2004 | -9.09 % change on previous year | +72.8% |
| 2005 | -8.41 % change on previous year | -7.5% |
| 2006 | -7.98 % change on previous year | -5.1% |
| 2007 | -7.25 % change on previous year | -9.1% |
| 2008 | -8.6 % change on previous year | +18.5% |
| 2009 | -9.91 % change on previous year | +15.2% |
| 2010 | -6.05 % change on previous year | -38.9% |
| 2011 | -13.41 % change on previous year | +121.6% |
| 2012 | -16.75 % change on previous year | +24.9% |
| 2013 | -18.1 % change on previous year | +8.1% |
| 2014 | 2.06 % change on previous year | -111.4% |
| 2015 | 5.76 % change on previous year | +179.2% |
| 2016 | 5.95 % change on previous year | +3.3% |
| 2017 | -0.6993 % change on previous year | -111.8% |
| 2018 | -1.81 % change on previous year | +158.8% |
| 2019 | -0.2374 % change on previous year | -86.9% |
| 2020 | -5.22 % change on previous year | +2096.5% |
| 2021 | -2.4 % change on previous year | -54.0% |
| 2022 | -3.74 % change on previous year | +55.8% |
Biggest year-on-year movements
Years where emissions of air pollutants, annual growth rate in Taiwan changed far more than this series normally does. A large move can be a real event or a change in how the figure was measured — the source note below says who published it.
| Year | Change | From | To |
|---|---|---|---|
| 1919 | +13350.9% | 0.0156 % change on previous year | 2.1 % change on previous year |
| 1960 | -11547.9% | 0.0556 % change on previous year | -6.36 % change on previous year |
| 1943 | +4485.4% | 0.1399 % change on previous year | 6.42 % change on previous year |
| 2001 | -2178.3% | 0.3087 % change on previous year | -6.41 % change on previous year |
| 2020 | -2096.5% | -0.2374 % change on previous year | -5.22 % change on previous year |
| 1950 | +1810.2% | 0.4852 % change on previous year | 9.27 % change on previous year |
Averages by decade
| Decade | Average | Lowest | Highest | Years |
|---|---|---|---|---|
| 1750s | 0.1682 % change on previous year | 0.1665 % change on previous year | 0.1697 % change on previous year | 9 |
| 1760s | 0.1649 % change on previous year | 0.1631 % change on previous year | 0.1664 % change on previous year | 10 |
| 1770s | 0.1612 % change on previous year | 0.1593 % change on previous year | 0.1628 % change on previous year | 10 |
| 1780s | 0.1571 % change on previous year | 0.1552 % change on previous year | 0.159 % change on previous year | 10 |
| 1790s | 0.1525 % change on previous year | 0.1506 % change on previous year | 0.1547 % change on previous year | 10 |
| 1800s | 0.1475 % change on previous year | 0.1455 % change on previous year | 0.1501 % change on previous year | 10 |
| 1810s | 0.142 % change on previous year | 0.1399 % change on previous year | 0.1451 % change on previous year | 10 |
| 1820s | 0.2018 % change on previous year | 0.1393 % change on previous year | 0.212 % change on previous year | 10 |
| 1830s | 0.26 % change on previous year | 0.2048 % change on previous year | 0.271 % change on previous year | 10 |
| 1840s | 0.2587 % change on previous year | 0.2536 % change on previous year | 0.2635 % change on previous year | 10 |
| 1850s | 0.282 % change on previous year | 0.2524 % change on previous year | 0.3129 % change on previous year | 10 |
| 1860s | 0.2773 % change on previous year | 0.266 % change on previous year | 0.3204 % change on previous year | 10 |
| 1870s | 0.278 % change on previous year | 0.2763 % change on previous year | 0.2807 % change on previous year | 10 |
| 1880s | 0.2561 % change on previous year | 0.2544 % change on previous year | 0.268 % change on previous year | 10 |
| 1890s | 1.24 % change on previous year | 0.2551 % change on previous year | 1.57 % change on previous year | 10 |
| 1900s | 3.42 % change on previous year | 2.04 % change on previous year | 5.36 % change on previous year | 10 |
| 1910s | 1.02 % change on previous year | 0.0156 % change on previous year | 2.36 % change on previous year | 10 |
| 1920s | 2.61 % change on previous year | -2.45 % change on previous year | 7.76 % change on previous year | 10 |
| 1930s | 2.03 % change on previous year | -0.4548 % change on previous year | 4.03 % change on previous year | 10 |
| 1940s | 2.14 % change on previous year | -9.9 % change on previous year | 8.58 % change on previous year | 10 |
| 1950s | 1.57 % change on previous year | -6.14 % change on previous year | 10.2 % change on previous year | 10 |
| 1960s | 1.7 % change on previous year | -6.52 % change on previous year | 13.42 % change on previous year | 10 |
| 1970s | 12.96 % change on previous year | 2.98 % change on previous year | 21.65 % change on previous year | 10 |
| 1980s | 7.83 % change on previous year | 4.42 % change on previous year | 14.16 % change on previous year | 10 |
| 1990s | 1.26 % change on previous year | -3.98 % change on previous year | 6 % change on previous year | 10 |
| 2000s | -6.91 % change on previous year | -9.91 % change on previous year | 0.3087 % change on previous year | 10 |
| 2010s | -4.33 % change on previous year | -18.1 % change on previous year | 5.95 % change on previous year | 10 |
| 2020s | -3.78 % change on previous year | -5.22 % change on previous year | -2.4 % change on previous year | 3 |
Countries ranked near Taiwan
- 202 Croatia -3.39 % change on previous year compare
- 203 Montenegro -3.43 % change on previous year compare
- 204 Brunei -3.51 % change on previous year compare
- 206 Niue -3.91 % change on previous year compare
- 207 Estonia -3.94 % change on previous year compare
- 208 New Zealand -4.37 % change on previous year compare
More climate change data for Taiwan
- Share of global CO₂ emissions and population 0.1% (2100)
- Share of global CO₂ emissions from oil 0.4% (2024)
- Share of global cumulative CO₂ emissions from cement 0.8% (2024)
- Share of cumulative CO₂ emissions from oil 0.5% (2024)
- Share of global CO₂ emissions from cement 0.3% (2024)
- Share of global CO₂ emissions from flaring 0.0% (2024)
- Per capita CO₂ emissions vs. per capita energy use 11.3 tonnes per person (2024)
- Share of global CO₂ emissions vs. share of population 0.7% (2024)
- Territorial vs. consumption-based CO₂ emissions per capita 11.3 tonnes per person (2024)
- CO₂ emissions per capita 11.3 tonnes per person (2024)
Frequently asked questions
- What is emissions of air pollutants, annual growth rate in Taiwan?
- Emissions of air pollutants, annual growth rate in Taiwan was -3.74 % change on previous year in 2022, according to Statizoid (derived).
- What is the highest emissions of air pollutants, annual growth rate recorded in Taiwan?
- The highest recorded value was 21.65 % change on previous year in 1978.
- What is the lowest emissions of air pollutants, annual growth rate recorded in Taiwan?
- The lowest recorded value was -18.1 % change on previous year in 2013.
- How does Taiwan rank for emissions of air pollutants, annual growth rate?
- Taiwan ranks 205th out of 219 countries with data for 2022.
- Is emissions of air pollutants, annual growth rate rising or falling in Taiwan?
- Over the last ten years it is up 77.7%. The long-run trend across the full record is volatile.
- Where does this Taiwan data come from?
- The figures come from Statizoid (derived), published as part of emissions of air pollutants, annual growth rate. Statizoid updates them automatically from the source API.
Download this data
CSV · JSON — 272 observations, free to reuse under Derived by Statizoid from the sources named on the page.
How this figure is calculated
The year-on-year percentage change in emissions of air pollutants. Computed from consecutive annual observations; years either side of a gap are skipped rather than bridged.
Computed from
- emissions of air pollutants Hoesly et al. (2024) – Community Emissions Data System (CEDS) – with major processing by Our World in Data
Statizoid computes this series; the underlying measurements belong to the publishers named above. The arithmetic is applied to every country and year where both inputs report, and nothing is estimated unless the page says so.
About this data
The year-on-year percentage change in emissions of air pollutants. Computed from consecutive annual observations; years either side of a gap are skipped rather than bridged.