Source: 2017 Canadian Open Math Challenge, Problem B3 Regular decagon (10-sided polygon) $ABCDEFGHIJ$ has area $2017$ square units. Determine the area (in square units) of the rectangle $CDHI$. [asy][asy] pair A,B,C,D,E,F,G,H,I,J; A = (0.809016994375, 0.587785252292); B = (0.309016994375, 0.951056516295); C = (-0.309016994375, 0.951056516295); D = (-0.809016994375, 0.587785252292); E = (-1, 0); F = (-0.809016994375, -0.587785252292); G = (-0.309016994375, -0.951056516295); H = (0.309016994375, -0.951056516295); I = (0.809016994375, -0.587785252292); J = (1, 0); label("$A$",A,NE); label("$B$",B,NE); label("$C$",C,NW); label("$D$",D,NW); label("$E$",E,E); label("$F$",F,E); label("$G$",G,SW); label("$H$",H,S); label("$I$",I,SE); label("$J$",J,2*dir(0)); fill(C--D--H--I--cycle,mediumgrey); draw(polygon(10)); [/asy][/asy]