These age preferences were confirmed in marriage records with males marrying females younger than them and vice versa.[38] A more recent study has supported these findings, conducted by Schwarz and Hassebrauck.[39] This study used 21,245 participants between 18 and 65 years of age who were not involved in a close relationship. As well as asking participants a number of questions on mate selection criteria, they also had to provide the oldest and youngest partner they would accept. It was found that for all ages males were willing to accept females that are slightly older than they are (on average 4.5 years older), but they accept females considerably younger than their own age (on average 10 years younger).