I tend to ignore GDP as an indicator because it's utterly useless. My favorite indicator is AGI, and the best indicators are things like per-capita income and proportion of money spent on things. Even those distort: in the 70s, you made $13k and spent $7k on a car; in 2014, you made $65k and spent $32k on a brand new Camaro--that's less, 49% instead of 53%--yet the damn Camaro has a much-better-engineered engine, suspension, drive train, electronic stability control, satellite navigation system, five-DVD MP3 changer, built-in Spotify, etc. Not to mention people tend to measure cost of the car by amortization of aggregate car payment, maintenance, fuel, insurance, and so forth.
I've given the 15-paragraph explanation of wealth growth over time too many times. People respond mostly by freaking out or mis-interpreting it as supply-and-demand economics (it's not even vaguely supply-and-demand), because it's a god damn brand new theory, because historians have briefly commented on things like the Industrial Revolution without actually writing the damn pattern down. The above is the short of it, so you can work out the unifying theory of economics yourself and figure out why it's hard to measure economic growth and productivity. Bonus points if you suddenly understand why supply doesn't just increase, instead of price; why some markets overcharge huge mark-ups, and how competition does and doesn't control this; and what technical condition will occur if communism is suddenly the correct economic practice.
Aside from that, a one-time cash infusion does very little, kind of like if you drop off 500 pounds of rice to an Ethiopian and never feed him again.