Respondent urges that records maintained by DD and Horseshoe, the two casinos at which petitioner gambled the least, see supra pp. 6-7, show that he had net gambling winnings for 2014. But these records were incomplete: The casinos kept track only of jackpots of $1,200 or more and other transactions where petitioner was using his rewards card. Petitioner credibly testified that he often did not use these cards, either because he forgot or because he believed not using the cards could change his luck. The casinos' records were thus biased, being more likely to show wins than losses.