You can see the downturn of the global financial crisis, whose roots lie in inadequate regulation of the banking sector, and you can see the gradient return to normal just before 2010, then you can see Conservative party policy take root and consistently underperform compared to the rest of recent uk history.
Guess what happens when you look at a national debt graph over the course of about a century! Guess which party fairly consistently gets us into worse debt and guess which party fairly consistently pays off national debt, then the word Projection may start to float around your mind.