Natwest (NWG) had the highest return between 2006 and 2009 by a large-cap US stock, returning 983,566.7%.

ASSET	YEARS	% RETURN
Natwest (NWG)	2006-2009	983,566.67%
Booking (BKNG)	2006-2009	878.54%
Mastercard (MA)	2006-2009	542.76%
Baidu (BIDU)	2006-2009	540.05%
CF Industries (CF)	2006-2009	504.8%
First Solar (FSLR)	2006-2009	452.65%
Trip Group Ltd ADR (TCOM)	2006-2009	397.48%
Ambev SA ADR (ABEV)	2006-2009	374.51%
Illumina (ILMN)	2006-2009	330.6%
Mosaic (MOS)	2006-2009	321.45%
Southern Copper (SCCO)	2006-2009	287.34%
Credicorp (BAP)	2006-2009	282.15%
Deckers Outdoor (DECK)	2006-2009	257.03%
Sociedad Quimica y Minera de Chile SA ADR B (SQM)	2006-2009	246.3%
Intercontinental Exchange (ICE)	2006-2009	207.67%
Petróleo Brasileiro SA - Petrobras (PBR.A)	2006-2009	203.45%
Petroleo Brasileiro Petrobras SA ADR (PBR)	2006-2009	201.3%
Vale SA ADR (VALE)	2006-2009	201.27%
POSCO (PKX)	2006-2009	192.15%
Apple (AAPL)	2006-2009	191.14%
Elbit Systems (ESLT)	2006-2009	183.72%
Amazon (AMZN)	2006-2009	183.38%
TechnipFMC (FTI)	2006-2009	180.78%
Align Technology (ALGN)	2006-2009	180.63%
Skyworks Solutions (SWKS)	2006-2009	176.61%

Large-cap stocks are treated as having a market cap of $10B+.