East 39th Street Commercial Corridor Plan by Chris Devins

SUPPLY & DEMAND ANALYSIS FOR HALF MILE TRADE AREA
Leakage is the difference between buying power and retail sales. It indicates how much residents
of an area spend that is not captured by actual sales by local stores. For example, if zip
code “X” has $70 million in expenditures by local residents on retail goods, and $30 million in
sales of retail goods by local stores, the leakage for “X” is $40 million. This tends to produce
a conservative estimate of leakage because stores sell to people outside the neighborhood as
well. Most neighborhoods have positive leakage because certain types of goods and services
are not normally purchased in the neighborhood. For example, you would not find major appliance
stores or large law firms in most neighborhood areas. The above chart shows that key
industry group categories in the immediate trade area show significant leakage. There is 100%
leakage in the Electronics and Appliance Stores category, also in Furniture Stores, meaning that
all shopping in these categories is done outside the trade area. There is a 100% leakage factor
in Specialty Food Stores, which indicates the same. A leakage factor of 57, such as that in
Grocery Stores, indicates that 57% of grocery shopping occurs outside the half-mile trade area.
The only negative leakage figure (above in red), in the half-mile trade area is the -$1,366,326 in
NAICS category 4453: Beer, Wine and Liquor Stores. This negative leakage means that customers
are coming in from outside the trade area to make purchases in the Beer, Wine and Liquor
Stores Category from the areas two liquor stores, which will be named later in the Exisitng
Land Use section. The numbers are similar at the 1 mile trade area also.
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