WHYY By Jewelers Row in the 700 block of Sansom Street as a demolition crew makes way for a new condo tower on Jan. 22, 2020. (Emma Lee/WHYY) Demolition work in Philadelphia dropped by more than half in 2020 — cheering preservationists but forecasting a possible slowdown in development projects heading into the New Year. Records from the city’s Department of Licenses & Inspections said that demo permit requests have fallen 54% from 2019. Although construction activity overall remained relatively strong in 2020 despite the pandemic, many analysts expect that economic blows linked to COVID-19 are taking longer to manifest in the construction trades. “We typically lag an economic recession by 12 to 18 months,” said Ben Connors, president of General Building Contractors Association. “This is a little bit different, so we do think there’s potentially a slowdown coming.”