UnitedHealth (UNH) had the lowest return in April 1987 by a US stock, returning -36.5%.

ASSET	MONTH	% RETURN
UnitedHealth (UNH)	April 1987	-36.48%
American Realty Investors (ARL)	April 1987	-34.92%
Rocky Mountain Chocolate Factory (RMCF)	April 1987	-31.82%
Williams-Sonoma (WSM)	April 1987	-29.9%
Franklin Resources (BEN)	April 1987	-28.55%
Range Resources (RRC)	April 1987	-27.78%
Best Buy (BBY)	April 1987	-25.75%
Research Frontiers (REFR)	April 1987	-25.37%
STAAR Surgical (STAA)	April 1987	-23.33%
Cullen/Frost Bankers (CFR)	April 1987	-22.65%
Acme United (ACU)	April 1987	-22.59%
Daily Journal (DJCO)	April 1987	-22.58%
AutoNation (AN)	April 1987	-22.37%
GEE (JOB)	April 1987	-21.74%
Flanigans Enterprises (BDL)	April 1987	-21.74%
ONEOK (OKE)	April 1987	-21.65%
Stifel Financial (SF)	April 1987	-21.34%
Barnwell Industries (BRN)	April 1987	-20.97%
RF Industries (RFIL)	April 1987	-20.14%
LCI Industries (LCII)	April 1987	-20.01%
Village Super Market (VLGEA)	April 1987	-19.05%
Cooper Companies (COO)	April 1987	-18.92%
HF Sinclair (DINO)	April 1987	-18.78%
Onto Innovation (ONTO)	April 1987	-18.75%
Arthur J Gallagher (AJG)	April 1987	-18.56%