Frequency

Distinct data values	$x_1,x_2,\dots ,x_n$ (sorted, no dup.)
Absolute frequencies	$f_1,f_2,\dots ,f_n$ — where $f_i$ is the frequency of $x_i$
Total number of data points	$N={\sum }_{i=1}^n{f}_i$
Relative frequency of $x_i$	$r_i=\frac{f_i}{N}$
Cumulative frequency of $x_i$	$F_i={\sum }_{j=1}^i{f}_j$
Relative cumulative frequency	$R_i=\frac{F_i}{N}={\sum }_{j=1}^i{r}_j$