Frequency Table (Histogram)
Bins	Midpoint	Abs. Frequency	Rel. Frequency	Cumul. Rel. Freq.	Density
[20,40[	30	2	0.033333	0.033333	0.001667
[40,60[	50	25	0.416667	0.45	0.020833
[60,80[	70	21	0.35	0.8	0.0175
[80,100[	90	7	0.116667	0.916667	0.005833
[100,120[	110	2	0.033333	0.95	0.001667
[120,140]	130	3	0.05	1	0.0025