Wednesday, December 18, 2013

The city's State of Cycling Report: An analysis

Photo from Streetsblog

I referred to the city's bloated State of Cycling Report the other day. Taking a look at the text between all that padding shows how desperate the city is to sell bikes to the people of San Francisco---and how unsuccessful that campaign has actually been, in spite of a lot of help from the local media.

After some preliminary pro-bike blather in the executive summary, page six indulges in the city's unconvincing numbers game about how many people are supposedly riding bikes in the city:

The US Census Bureau’s American Community Survey (ACS) shows a 66% increase in bicycle commuters from 2002 (2.1% of work trips) to 2010 (3.5% of work trips), putting San Francisco third in the nation behind Portland, Oregon (6%) and Seattle, Washington (3.5%) in ridership among major US cities. Annual bicycle counts have more than doubled between 2006 (4,862 riders) and 2011 (10,139) at sampled locations. Two statistically significant random surveys of San Francisco residents during 2011 show that about 3.5% of all trips in the city are taken by bicycle, demonstrating that the ACS, local surveys and bike counts all corroborate one another to show steady increases in cycling.

Playing the percentage game puffs up the increases: Yesterday I ate cereal for breakfast, and I ate cereal again today, a 100% gain in breakfast cereal consumed in only two days!

The 2.1% of bicycle commuters in SF percentage goes back to 2000; pushing it up to 2002 is a bit of petty fudging that only shows how desperate the city is to sell a positive interpretation of these unimpressive numbers.

And the "annual bicycle counts" that "have more than doubled" between 2006 and 2011 are only of bike commuters, not of citywide cycling:

Two statistically significant random surveys of San Francisco residents during 2011 show that about 3.5% of all trips in the city are taken by bicycle, demonstrating that the ACS, local surveys and bike counts all corroborate one another to show steady increases in cycling.

The "surveys" reference is apparently to the MTA's Mode Share Survey that found that only 3.4% of all trips in the city are by bicycle. Though that increase has been "steady," it hasn't been impressive: From 2.1% in 2000 to 3.4% in 2011, a gain of only 1.3% in ten years. The city would trumpet that as a 62% gain, but the rest of us have a right to be unimpressed.

I'll say it again: These numbers are seriously flawed, since the percentage of all trips by bicycle must be higher than the percentage of commuters by bicycle, a subset of all trips by bike. Since the Mode Share Survey methodology seems pretty solid, the original ACS percentage of bike commuters way back in 2000 must have been inflated, thus skewing all subsequent percentages higher than they really are.

This fundamental problem with the numbers is now joined by the city's shocking failure to accurately account for all the cycling accidents in the city by systematically not counting many such accidents recorded at the city's primary trauma center, San Francisco General Hospital. Instead, the city has relied entirely on police reports to calculate the number of cycling accidents in San Francisco.

Page six touches on the safety issue:

The ratio of bicycle trips to bicycle collisions remains constant. Unsafe bicycle riding behaviors (sidewalk bicycle riding and wrong-way bicycle riding) remain infrequent overall and take place on roadways that are deficient in proper facilities.

This is simply untrue. Are they being dumb, or do they think we're dumb? Hard to say. The city's Collision Report on all accidents on city streets says that injury accidents to cyclists are actually increasing, even in the context of the city's systematic under-count of these accidents:

Injury collisions involving bicycles, however, have increased as a share of the City’s reported injury total. From 2000 to 2004, ten percent of collisions involved a person riding a bicycle. Eleven years later that percentage has doubled to 21 percent as bicycle collisions have increased while other types of collisions have not (page 17).

Also according to the city's Collision Report, cyclists are responsible for half their own injury accidents by "unsafe bicycle riding behaviors" unmentioned by the State of Cycling report, like speeding and running stop signs (page 24).[Later: Wrong! Actually the report does mention that behavior on page 40.]

Page 7 continues the behavior falsehood by saying under "Bicycling Behavior" that 94% of cyclists ride legally, only 2% ride on sidewalks, and only 1% ride the in the wrong direction on city streets, as if these were the only serious bad behaviors by cyclists.

More on this report later.

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