It's rough news on a Monday but you are, indeed, ageing.
It's a tough pill to swallow, especially because 'Tik Tok' now means something dramatically different to the longest-running number 1 single of 2009.
This time, a decade ago, a little known artist - Ke$ha (Kesha Rose Sebert) shot to the top of the ARIA charts with her debut single, 'Tik Tok'.
This stayed in prime position for 8 consecutive weeks and was probably one of the songs you best remember singing in the back of the car.
Now Tik Tok is best known as a social media platform. My, my - how the time does fly.