Which of the following provided a clue about the timeframe of A Girl Named Zippy?

Everyone familiar with my childhood in Mooreland agreed with Melinda’s position.
We tried a variety of hairstyles in those early years.
I decided to go play rodeo on my bicycle with the purple banana seat and the sissy bars.
Many large, predatory birds believed I was asking for a date.

The sentence "I decided to go play rodeo on my bicycle with the purple banana seat and the sissy bars." provides a clue about the timeframe of A Girl Named Zippy.