It may surprise some to learn that New York is the most forgetful city when it comes to ride shares. So says Uber, which has released its ninth annual Lost & Found Index — a hilarious, surprising and occasionally gross list of stuff riders left behind in cars last year. (Miami, Chicago, Los Angeles and Washington, D.C., were close behind New York in obliviousness.)

In reporting the data, the San Francisco ride-share behemoth also noted that it was doing so just as the planet Mercury was coming out of retrograde, a time astrologers claim has an effect on forgetting.

On April 5 alone, more than 7,000 riders reported lost items last year.

“Things get glitchy” during a Mercury retrograde, said Quinn Cox, an author and astrologer based in Provincetown, Mass. That explains the April number, but there was no clear cosmic rationale for why people lost the most things on Oct. 26, according to Uber’s report, than on any other day of the year, he added, “although that is Hillary Clinton’s birthday.”

Volume may be a factor in the quantity of losses suffered by New Yorkers. Possibly, too, there is the stress of congestion fares to consider or the demands of living in a demanding and absurdly expensive metropolis.

Yet people everywhere misplace their belongings in ride-shares and they do so with surprising specificity, according to data assembled by Uber. It may help to know when leaving the house on Mondays that you are likelier to lose your gloves in a ride-share on that day than any other. Tuesdays, it’s jackets. Wednesdays are medicine. Mind your umbrella if you happen to hail an Uber on Thursday or Friday. On Saturdays, hold on to your cowboy hat.

Why debit card losses peak on Sundays is destined to remain a mystery — as is so much about the Uber Lost & Found index. Never mind how passengers forget such items: Why do passengers board a vehicle with a urinal, a turtle, a chain saw or a mannequin head with human hair?

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