I. "Prom Stats" Infographic:

2014 National Average:  http://www.foxbusiness.com/personal-finance/2014/04/09/prom-spending-falls-for-first-time-in-3-years/
Limo/New Dress: http://www.statisticbrain.com/prom-night-statistics/
Tux Rental:  http://www.startribune.com/local/west/18536439.html

II. "promRED Ideas" Infographic:

2014 National Average: http://www.foxbusiness.com/personal-finance/2014/04/09/prom-spending-falls-for-first-time-in-3-years/

III. Case Study

2014 National Average: http://www.foxbusiness.com/personal-finance/2014/04/09/prom-spending-falls-for-first-time-in-3-years/
Limo/New Dress: http://www.statisticbrain.com/prom-night-statistics/
Tux Rental:  http://www.startribune.com/local/west/18536439.html