This chart shows a key reason why millennial parents are miserable

• Millennial parents are overwhelmed by the amount of toys their young kids have.
• The price of toys has gone WAY down in the last 30 years, while nearly everything else is costlier.

If you're the parent of young children, you may be dreading one aspect of the holiday season: accumulating more plastic toys. Despite millennial parents' best efforts to keep the junk at bay, somehow the toy bin keeps overflowing, and the Hot Wheels cars, knock-off Magna-Tiles, dolls, blocks, and Legos seem to always be underfoot.

Suddenly it seems like all the parents I know are trying to find ways to cut down on the amount of toys (often from well-meaning relatives) flowing into their homes.

This sounds like a champagne problem — spoiled rich kids with too many toys.

But the data shows another side of the story.

There's an economic reality to why kids today seem to have way more toys than we did: toys are way, way, way cheaper than they were 30 years ago.

The US Bureau of Labor Statistics tracks the Consumer Price Index, which is basically the inflation rate for different categories of goods and services, like education, medical care, housing, or groceries.

Toys as a category has had significant deflation — meaning they've gotten way cheaper in the last 30 years. This is due to a handful of factors, but mainly increased reliance on cheap overseas production.

Simply put: a toy that cost $20 in 1993 would only cost $4.68 today.

It's easy to notice some of this in stores. You can buy a Barbie for $11.99 onAmazon right now — that's around the same prices as I remember Barbies being when I was a kid in the early 90s.

Compare the deflation of toy prices to another thing that parents of young children spend a lot on: childcare.

The cost of daycare and preschool is up more than 200% since 1993. That means daycare tuition of $500 per month in 1993 is equivalent to roughly $1,600 per month today. Ouch.

Consider this: Babysitter rates are around $17 to $20 per hour, depending on your area, according to Care.com. That means a three-hour date night to the movies will run you about $50 to $60. (And don't expect grandparents to help out: many millennial parents say they can't count on their boomer parents to babysit).

For that same amount, you can buy a toy drone ($19.59) AND a flamingo that sings and poops on a toilet ($34.01).

No wonder parents are so stressed out.