The growth might not look like much at first. But after decades of decline, this Next City GIF shows just how much of a comeback Philadelphia is making.

The dark colors represent density of housing development. The GIF shows a boom from 1930s to the 1960s before growth began to decline in Center City and much of the surrounding area for around 40 years, save for a few pockets in any given decade. The decade following 1990 shows the least amount of growth, but come 2000, Center City began to develop. The growth has continued into this current decade as more neighborhoods redeveloped and re-purposed housing.

The development mimics population shifts in Philadelphia. From 1930 to 1960, Philadelphia had nearly 2 million residents. In the 1970s, the population began to decline and didn't show growth until the 2010 Census. The steady growth in the past decade was due in part to a new wave of immigrants, just like a century before.