Judging by the massive price hikes right next to being told that Inflation is much lower percentage-wise than the price increases most people are experiencing, that Official Real Income growth number is based on doing the Maths with an Official Inflation that hugelly underreports real inflation.

Do the Maths with an Inflation figure that's not as bullshit as the current Official one and you get negative Real Income Growth.

Similarly for GDP Growth, by the way: Official Inflation numbers which understate the real inflation mathematically yield higher Official GDP Growth numbers.

There are very big political reasons to fiddle with the Inflation reporting to make it seem lower because it boosts up several important Economic figures without fiddling with those directly, and the pressure from politicians to do so is probably manyfold the normal in an election year.