Women are grumpier than men

This article here states the following:
"Here is an optimization strategy for finding out a house’s probability of participating in Halloween. If the wife is aged between 41 to 50, and the husband 51 to 60, there is 100% chance that you will get a treat. It dramatically reduces down to 25% if the wife is older than 51 and husband has passed his 60th birthday. Similarly, if either of the couple is aged more than 71, you are less likely to get any treats."

So there we have definitive scientific proof that women become grumpier faster than men, well at least from the age of 50...