Kids cashed in at an average of $3.70 per lost tooth last year, down 43 cents from 2017, Delta Dental Plans Association, one of the nation’s biggest dental insurance collectives, said Thursday.

It’s the second straight year the tooth fairy has played Scrooge in the annual survey, which Delta Dental has conducted for 21 years. As recently as 2016, parents — um, the tooth fairy — paid out $4.66 per tooth. That’s a drop of almost 21 percent in two years.