The annual $3600 membership fee at the Oak Meadows Golf Club is due at the beginning of the year. Instead of a single “lump” payment, a member can pay $1600 at the start of the year and defer the $2000 balance for five months by paying a $75 surcharge at the time of the second payment. Effectively, what annual rate of simple interest is Oak Meadows charging on the $2000 deferred payment?