The AEL (aid effectiveness literature) studies the macroeconomic effects of development aid using cross-country or panel data econometrics. It contains 97 papers of which 43 study whether development aid leads to increasing accumulation. The aggregate results of the 43 studies are that aid increases investment with about 25% of the aid, while most of the remaining 75% of the effect is crowded out by a fall in savings. However, these aggregate results are so variable that it is dubious if accumulation rises.