I'm fortysomething and most of my contemporaries are shorter than I am.

Don't forget that as people get older, they tend to get shorter. Cartilage breaks down in the back and joints, and people start to stoop. My grandmother was 5"9" most of her adult life, but less than 5" when she died at age 95. It happens even at my age...I've lost about an inch from my teenage height of 5'10".

Also, check other people's shoes. I was stunned to not be a giant when I visited Japan in 1998, until I noticed all the girls wore 5" platform shoes.