I can't find any problems with the data, but this is extremely unintuitive! My father who was buying shares decades ago for his personal account had $50 commiss

I can't find any problems with the data, but this is extremely unintuitive! My father who was buying shares decades ago for his personal account had $50 commission fees (not inflation adjusted!!) And like most brokers in that time demanded, he could only buy in 'lots' meaning 100 shares minimum or multiples of that. You had to place a call to your broker, usually when the market was open, which meant the middle of the work day. Today, practically everyone including fastfood workers has access to 401ks which are extremely cheap. No commission fees upfront. Almost every broker has commission free trading. Not only can you buy 1 share at a time, you can buy fractions of 1 share. You can do it all from your phone, after or before market hours. Access has been expanded and costs lowered dramatically. So why have the bottom 90% stopped buying shares?