Substantial evidence exists that the solar irradiance incident at the surface has declined substantially over the last 50 years (with a potential increase in diffuse radiation), pointing to the inclusion of diffuse radiation in models [72].
Landscape health has declined substantially in many areas.
Over the last 40 years smoking has declined substantially.
After years of strong growth in coal use, the rate of growth has declined substantially".
At the same time, by all accounts, the number of closings has declined substantially.
Although Time's circulation has declined substantially, the drop off isn't as big as some people think.
Yet timber production has declined substantially, and subsequent federal subsidies have not compensated for the decline.
While small earthquakes are still occurring in the area, their frequency has declined substantially.
Over the last few decades, engagement in physical activity – even walking – has declined substantially, with serious impacts on population health.
Over the last two decades the number of large, independent -- so-called Class I -- freight lines has declined substantially.
More importantly the volume of sea ice has declined substantially since 1979, as the ice has thinned.
