Halloween costumes were pretty wild in the '70s. Reed Saxon/AP

The way people celebrate the spooky season has evolved over the decades, from homemade costumes and neighborhood parties to school parades and elaborate haunted houses.

For instance, if you went to a Halloween party in the 1940s, chances are you'd be bobbing for apples. In the 1970s, you'd probably be covered in glitter paint.

Each year, the amount of money Americans spend celebrating the holiday seems to grow, too. This Halloween, Americans are expected to spend a record $13.5 billion, the National Retail Federation reported, citing its annual survey.

However, while spending is up from last year, respondents said they were more likely to shop for a costume at discount stores versus specialty Halloween costume stores or online.

Here are 20 vintage photos that show how Halloween celebrations have changed through the years.

Bobbing for apples on a string was a popular Halloween party game in the 1930s.

Bobbing for apples in 1939.…