In the past forty years, Beijing experienced considerable urban
expansion. The area of urban land in 1972 was 861 km2, accounting
for 5.26% of the total area. In 2010, urban land increased to
2666 km2 and comprised 16.28% of the total area (Table 4).
More than 1800 km2 land was urbanized during the period from 1972 to 2010. The period from 1992 to 2000 had the highest annual
expansion rate (58.91 km2/yr), followed by the periods from 2000
to 2010 (56.78 km2/yr), 1972 to 1984 (40.51 km2/yr), and 1984 to
1992 (35.02 km2/yr) (Table 4).