Citi Bike annual trips (NYC)Serena Williams WTA titles per year
New York Citi Bike trips climbing as Serena Williams's annual WTA title count slips. The negative correlation is just the calendar of one career winding down as one city's bike-share programme ramps up. Two completely unrelated graphs of New York at different paces.
Serena Williams's WTA title count per year declined across this window as her career entered its later phase before retirement in 2022. Citi Bike annual trips grew from about 9 million in 2013 to over 30 million by 2020 as the network expanded into Brooklyn, Queens, and the Bronx and added e-bikes. Two completely unrelated lines on opposite trajectories sharing a window because the same seven years saw one tennis career mature toward retirement and one city mobility programme reach its network-effect tipping point.
One career wound down. One bike share scaled up. The decade had room for both kinds of transition.
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