Caledonia Mining (CMCL) had the highest return between 1984 and 1986 by a US stock, returning 788,805.8%.

ASSET	YEARS	% RETURN
Caledonia Mining (CMCL)	1984-1986	788,805.77%
MDU Resources (MDU)	1984-1986	24,158.33%
Franklin Resources (BEN)	1984-1986	1,247.62%
PLDT Inc ADR (PHI)	1984-1986	861.43%
Nike (NKE)	1984-1986	607.32%
Tyson Foods (TSN)	1984-1986	581.9%
Gap (GAP)	1984-1986	578.77%
Loews (L)	1984-1986	565.43%
Badger Meter (BMI)	1984-1986	557.98%
Escalade (ESCA)	1984-1986	438.45%
CECO Environmental (CECO)	1984-1986	423.8%
Teva Pharma Industries Ltd ADR (TEVA)	1984-1986	387.87%
Church & Dwight (CHD)	1984-1986	380.88%
Tejon Ranch (TRC)	1984-1986	378.59%
Westamerica Bancorporation (WABC)	1984-1986	377.31%
United Fire (UFCS)	1984-1986	356.12%
Tootsie Roll Industries (TR)	1984-1986	352.48%
Paychex (PAYX)	1984-1986	350%
CEL-SCI (CVM)	1984-1986	342.86%
American States Water (AWR)	1984-1986	331.18%
Oil-Dri Corporation Of America (ODC)	1984-1986	308.87%
Crown Crafts (CRWS)	1984-1986	300.04%
Seaboard (SEB)	1984-1986	299.41%
Reading International (RDI)	1984-1986	299.07%
Arthur J Gallagher (AJG)	1984-1986	293.5%