Is the Prom Getting Cheaper Over Time?

OMG, it’s prom season again!  This weekend was my daughter’s junior prom and before the big event a dozen teenagers and their parents were at my home for “pre-prom” pictures.  After the last couple left I did the natural thing for both parents and economists; I started totaling up the various bills for the event.  A strange thought crossed my mind.  Compared to my older children’s and my own experience, the total price tag for this year’s prom was high, but not as outrageous as in the past.  Could it be that proms are actually getting cheaper over time?

Today I gathered data from the US government’s Bureau of Labor Statistics website and found it is true.  Proms really are getting cheaper over time.

Each month, the Bureau releases the Consumer Price Index (CPI) to track inflation.  Since 1998, the CPI has increased 43%, which means that the average item a family bought in 1998 for $1 now costs $1.43.  The CPI doesn’t track the prom directly.  However, it releases each month hundreds of detailed price indexes so that anyone can see, for example, if the price of breakfast cereal is rising faster than doughnuts over time.

I created a Prom Price Index from ten of the CPI’s components (more details are found in Chapter 6 of my textbook ).  The CPI directly tracks the price change for many prom items, such as “Women’s dresses,” “Women’s shoes,” “Men’s suits,” “Men’s shoes,” “Photographer fees,” “Haircuts,” and “Beer,” which covers the age-old tradition of sneaking in a drink when the adults are not looking.  The CPI does not specifically cover limousine rentals, corsages, boutonnières, and bouquets, but does track “car rentals” and “indoor flowers,” which are pretty close categories.  The hardest category to match was the cost of prom tickets.  This is not as much of a problem as I expected because the price of the ticket turned out to be only a small part of the total cost.  The closest category was “full service meals,” even though from the stories I heard almost none of the attendees spent much time actually eating.

Combining these ten categories — based on roughly how much my daughter and her friends spent — showed that, since 1998, the price of going to the prom went up by 17%, which is less than half of the 43% increase seen in overall prices.  (If you want to calculate the change using the amounts of money you spent, download the Excel spreadsheet PromPriceIndex  here)

Below is a graph starting in 1998 that shows how $100 spent on items in the general consumer price index (CPI) changed and how $100 spent on the ten categories making up the prom index changed.  The general CPI steadily marches upward, while the prom index does not start going up in price until 2005.

Why is there such a big difference?  The answer is clothing and shoes.  We expect cell phone and laptop prices to fall year after year.  But other things, like clothing and shoes, have also fallen in price or increased only a small amount.  For example, the average man’s suit cost 13% less in 2013 than it did in 1998.

Proms will never be cheap.  However, it is nice to know that over time the real cost of attending this rite of passage is falling.