This is a chart of coefficient of lift and drag for the NACA-0015 at Reynolds number 2,000,000 taken from "Aerodynamic Characteristics of Seven Symmetrical Airfoil Sections Through 180-Degree Angle of Attack For Use In Aerodynamic Analysis of Vertical Axis Wind Turbines" The study only examined Angle of Attacks from 0 to 180 degrees. I mirrored the data for the region between -180 and 0 degrees.

Also plotted on this chart are two formulas I devised to estimate values for the coefficients of lift and drag through 360 degrees. While my formulas diverge greatly near 0 and 180 degrees AoA, they track rather closely the area were the flow over the wing is stalled. That is the area between about 20 and 160 degrees AoA

The formulas I used are:

Stall = (IF(ABS(alpha)>90;-0.95;1)*ABS(COS(alpha)))

Cl = SIN(alpha)*(Stall)*2.1

Cd = (1.8-0.007)*(SIN(alpha))^2+0.007

This chart uses a simpler formula for Coeffecient of lift

Cl = SIN(alpha * 2)* 0.93