Here's what happened:
* Early 1960s: Most comics were still priced at 12 cents.
* Mid-1960s: Some publishers started experimenting with higher prices, like 15 cents.
* Late 1960s: The price of most comics began to settle around 15 cents.
Therefore, it's incorrect to say there was a definitive jump to a single price in 1969. The transition to 15 cents occurred gradually throughout the late 1960s.