Bridge Tolls
Advocacy Project

Income Progressivity Calculations

Will East River bridge tolls be "progressive" with respect to income? We answered this question with a resounding yes in Section 7 of the BTAP "Who Will Pay?" report. We noted that residents of Brooklyn, Queens and Staten Island who drive to work on an East River bridge earn, on average, some $14,300 a year more than their working neighbors who don't. Here we present our methodology.

In a certain sense, of course, the tolls are inherently progressive. That is because lower-income citizens tend to be heavier users of municipal services such as schools, transit, parks and social services that tolls will help rescue from cutbacks. Thus, the tolls could have a net progressive effect even if they were paid equally by rich and poor families. (This point was articulated in a broader context in City Limits recently by J.W. Mason, policy co-ordinator for the Working Families Party.)

Nevertheless, it's important to examine the progressivity of East River bridge tolls in the usual sense of whether they will be borne more heavily, relative to income, by well-off people than by those with lower incomes. Here's how we did the analysis.

Our data source was a subset of U.S. Census data called PUMS (Public Use Microdata Samples) based on detailed surveys of a sub-sample of the total population, extracted for us by the data-analysis service Infoshare. To keep the numbers manageable, we confined our analysis to residents of Brooklyn, Queens and Staten Island; they account for nearly two-thirds of regular East River Bridge users (see Table 1 of "Who Will Pay?"). Since PUMS data aren't yet available from the 2000 Census, we employed 1990 PUMS data.

Let's take residents of Brooklyn, for illustration. The 1990 PUMS data show 908,429 Brooklyn residents working at jobs in New York State (we excluded out-of-state commutes). We divide them into two groups: a small group, 43,449, who regularly drive a car, truck or van into Manhattan; and a large group, 864,980, who don't, either because they take transit into Manhattan or because they work in a borough or county other than Manhattan and therefore don't have to cross the East River to get to work.

To break down worker income by county, Infoshare uses "bins" of varying "widths." The bins are $5,000 wide for worker incomes up to $40,000 a year, e.g., $15,000 to $20,000. The bins are wider at the less-populated higher-income levels, e.g., there is one bin for $60,000 to $75,000, another for $75,000 to $100,000, and so forth.

Since we want to calculate the mean (average) income for each of the two groups, we had to assign a single income value to each bin. We made the default assumption to approximate the mean for each bin by its midpoint. Thus, workers in the $15,000 to $20,000 bin are assumed to have an average income of $17,500, for example. With this simplifying assumption we were able to calculate the average income for the two groups of Brooklynites: $34,117 for those driving to Manhattan, and $24,567 for all others.

These figures represent 1989 earnings levels. We raised them to 2002 levels in two steps. First, we multiplied by 1.434, denoting the overall inflation rate from 1989 to 2002, as measured by the Consumer Price Index for Urban Wage Earners and Clerical Workers (Source: http://www.bls.gov/data/). Second, we applied the national average increase in real (inflation-adjusted) weekly earnings from July 1989 to July 2002, which we calculated to be 1.053, based on data from the federal Bureau of Labor Statistics in response to our on-line request The product of the two ratios is 1.510, indicating that, on average, workers in 2002 earned $1.51 for each $1.00 they earned in 1989.

Applying that multiple to the 1989 income figures above yields $51,515 for the average 2002 income of the 43,449 Brooklynites driving to work in Manhattan, and $37,095 for the 864,980 working Brooklynites who don't drive to jobs in Manhattan. Now we have to adjust these figures for the fact that not all of the 43,449 Brooklynites in the first group will be affected by East River bridge tolls, since some of them cross into Manhattan on an MTA tolled facility (the Brooklyn-Battery Tunnel).

In "Who Will Pay?," we estimated that 16% of all Brooklynites driving into Manhattan use the tunnel and thus already pay a toll. (See text box, p. 5.) Therefore, to accurately compare Brooklynites who will be affected by the tolls with those who will not, we must move 16% of the group of 43,449 — 6,952 people — into the group of 864,980.

We know of no way to distinguish the incomes of these 6,952 Brooklyn commuters who drive to Manhattan through the tunnel from the other 36,497 Brooklyn commuters who drive to Manhattan on an East River bridge. It may well be that the 6,952 are somewhat more affluent, on average, than the other driver-commuters, since they are choosing a tolled facility over a free bridge. Unfortunately, there is no way to confirm or quantify this. On the other hand, the mean income figure for all 43,449 drivers may overstate that for car-commuters alone, since the group includes not just motorists but van and truck drivers, who tend to be paid less well than ordinary office workers. (Our "car-truck-van" category could not be subdivided.) If that were the case, then the two deficiencies in the data would tend to be offsetting.

In any event, our Brooklyn results are as follows:

Workers living in Brooklyn                        Number      Mean Income, 2002
Group that will pay East River bridge tolls       36,497          $51,515
Group that won't pay East River bridge tolls     871,932          $37,210
Difference                                                        $14,305

Thus, the difference between the mean incomes of the two groups of Brooklynites - between those who will be newly tolled regularly en route to work, and those whose toll status will be unchanged by imposition of tolls on the East River Bridges - is $14,305.

We employed the same procedure for Queens and Staten Island, moving the estimated shares of each borough's car-commuters to Manhattan who use a tolled crossing, into the large group that won't be affected by new tolls on the East River bridges. (These percentages are 50.1% for Queens and 24.4% for Staten Island, as noted in the text box on p. 5.) Here are the results:

Workers living in Queens                           Number      Mean Income, 2002
Group that will pay East River bridge tolls        30,961          $51,891
Group that won't pay East River bridge tolls      883,326          $39,440
Difference                                                         $12,451
 
Workers living in Staten Island                    Number      Mean Income, 2002
Group that will pay East River bridge tolls        11,797          $63,648
Group that won't pay East River bridge tolls      163,966          $47,697
Difference                                                         $15,950

Among the three boroughs, Queens has the smallest differential between the means of the two groups, $12,451, while Staten Island has the largest, $15,950.

The last step is simply to combine the three boroughs by weighting the respective mean incomes by the number of workers:

Workers living in Bklyn, Queens or S.I.            Number      Mean Income, 2002
Group that will pay East River bridge tolls        79,255          $53,468
Group that won't pay East River bridge tolls    1,919,224          $39,132
Difference                                                         $14,336

The mean income of the group that stands to pay East River bridge tolls regularly is 37% greater than that of the unaffected group. The $14,336 difference in annual earnings is 9.5 times the $1,510 in bridge tolls that an East River bridge commuter can expect to pay annually once the bridges are tolled (see "Who Will Pay?," Table 5).

The rest of this page presents possible refinements of these calculations.

Medians
Medians allow us to compare the two groups without the extra weighting attached to cases with very high incomes. Following are the median incomes of the respective groups (East River bridge commuters, and all other workers), in 2002:

                                    Bklyn     Queens       S.I.    3 Boro's
Group that will pay East
   River bridge tolls             $41,319    $43,416    $52,946     $43,869
Group that won't pay East
   River bridge tolls             $31,272    $34,504    $36,417     $33,199
Difference                        $10,046    $ 8,912    $16,530     $10,670

(The three-borough average is weighted by the number of workers shown above for each borough.)

Using medians rather than means narrows the income difference between daily East River bridge users and other jobholders from the same boroughs, from $14,336 to $10,670.

After-tax Income Differences
Most though not all car commuters pay their travel costs out of their own pocket, with after-tax rather than pre-tax income. Using a standard Web-based tax calculator, http://www.4nannytaxes.com/, we estimated the take-home pay for wage-earners (each with three additional dependents) earning the respective mean income for the two groups. The higher-income worker retains $40,772 of her gross income of $53,468, while the lower-paid worker retains $31,224 of her $39,132. The difference between the respective after-tax incomes is $9,548, which is more than six times as great as the $1,510 in annual tolls that a solo (non-carpooling) commuter will pay to use an East River bridge.

Carpooling
A third of current East River bridge commuters carpool (see "Who Will Pay?," Table 6), and presumably more will do so to split the cost of tolls. With two in the car instead of one, the annual toll cost drops from $1,510 to $755. This per-capita cost (for a two-person carpool) is covered 19 times over by the differential between the mean pre-tax incomes, almost 13 times by the after-tax difference, and 14 times by the difference between the median pre-tax incomes.

Transit Fare Hike
Some argue that the toll cost facing East River-using drivers should be netted by the jump in commuting costs for transit users. A year-round transit commuter can expect to pay $123 more per year, on average, starting in May, when the fare hike takes effect. (We calculated that figure by multiplying the 30.3¢ difference between the new bulk-discount fare of $1.667 and the old $1.364 rate, by 405 annual transit trips estimated in Section 6 of "Who Will Pay?.") Netting that amount from either the $1,510 annual toll cost for a solo commuter or the $755 cost for a 2-person carpool would increase the extent to which the toll cost to a typical East River bridge commuters will be covered by his or her income advantage.

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