you have the following assumptions and spot rates - solve for the implied forward rates
	t0	t1	t2	t3
One-year rate	1.330%	???	???	???
Two-year rate	1.590%	???	???
Three-year rate	1.810%
Four-year rate	2.030%

Implied forward 1 year rate t+1f1 X			at time t+1 (in one year)
Implied forward 1 year rate t+2f1 x			at time t+2 (in two years)
Implied forward 2 year rate t+1f2 x			at time t+1 (in one year)
Implied forward 1 year rate t+3f1 x			at time t+3 (in three years)
Implied forward 2 year rate t+2f2 x			at time t+2 (in two years)