https://www.pennlive.com/news/2016/12/get_ready_for_another_gas_tax.html

3 times the gas tax has gone up prior to this last one.

And apparently, you glossed over the most important part of the article as to why it’s going up this year:

A provision in the law sets the "floor" of the wholesale gas price at $2.99, PennDOT says. If the price remains above this level for 12 months, the fuel tax rate increases. The average wholesale price is now $3.17.

So total, the gas tax has increased 4 times.