What data do you need to demonstrate that West Germany did better than East Germany?
You need a definition of "better" than lends itself to measurement, then observations regarding the variables you picked to make the comparison.
I never made the argument East Germany performed better than West Germany. As a matter of fact, I never looked into that kind of issue. However, there is an enormous difference between a centrally planned economy and someone who argue about, say, transfers dedicated to pay health care.
Are you ignorant of data that shows Florida doing better than Cuba or that Formosa did better than Red China or that Obama was only president not to have one year of 3% growth?
I never looked at data regarding Florida, Cuba or Formosa. Which variable did you choose, for which period and how did you aggregate them into a sort of index that allows you to say X is better than Y?
Obama also served in the worst recession since the 1930s.
He got into office in january 2008, so he can't be blamed for financial institutions racking up on credit derivatives during the whole 2000s, nor for home buyers signing variable interest rate mortgages when the Federal Reserve decided against all common sense to lower its rate before making it soar back up. That's 2003-2006, by the way, under President Bush at the Whitehouse and Allan Greenspan's tenure at Federal Reserve. Credit delinquancy rates rose before Obama even won the election, let alone did anything.
But if you want to play like a moron with data (which you probably didn't check), if you look at Republican vs Democrat presidency, the average growth rate of real GDP was higher under Democrat presidents over the last 70 years. The reason is simple: Democrats mostly got the Whitehouse at the right time (which is, in the more distant past). Once you control for that trending effect, nothing is left and who controls the Whitehouse has no statistically significant impact on real GDP growth in the US.
If you're going to make comparisons, compare apples with apples and run the appropriate regressions on actual data or draw your conclusions from people who did. "Cuba grows slower than Florida, hence all welfare programs suck" is an absurdly stupid statement to make.