open greene8_3.gdt
genr q_A = q/A
genr kinv = -1.0/k
logs q_A k
ols q_A const l_k
ols q_A const kinv
ols l_q_A const l_k
ols l_q_A const kinv
gnuplot q_A k
genr dum = year > 1942
ols q_A const l_k dum
ols q_A const kinv dum
ols l_q_A const l_k dum
ols l_q_A const kinv dum
ols q_A const l_k 
chow 1943
ols q_A const kinv
chow 1943
ols l_q_A const l_k
chow 1943
ols l_q_A const kinv
chow 1943
