That's not true. "Statistical" (presuming you mean statistically), there is no way to prove which political wing has improved people's lives more.

The greatest leap forward (in terms of GDP, population levels, technology and life expectancy) was the industrial revolution (even Marx congratulate the bourgeoisie on their achievements that exceeded any civilization before in such a short time in the opening of the Communist Manifesto). This did come with massive exploitation and wealth inequality but in most people's opinions the good of it outweighs the bad.

Furthermore, right wing ideas have provided stability to nations for centuries (look at Burke and his ideas of slow gradual reform or Hobbes and his idea of the role of the state).

Left wing governments did guide the Western world to social democracy which has been successfull so far but seems to be slowing down.

But left wing governments have also been responsible for Maoism, Stalinism, The Red Terror, etc. Whereas right wing governments have been responsible for Fascism, Pinochet, Nazism etc.

There is no clear winner between the two political wings. It's almost like you should look at each policy independent of origin and debate it on its merits (regardless of its left wing or right wing) rather than viewing everything through partisan lenses.

Yeh i can believe that is statistically true, but personally I think moderate right-center parties are almost equally good as most Centre-left parties, but I also believe that far-left governments are usually better than far radical-right parties are a lot worse. These are just my personal opinions though.