160 people are asked how many siblings they have?

The (incomplete) results are shown below (Please use 4 decimal places when apply):

# of Siblings	Frequency	Relative Frequency	Cumulative Frequency
0		0.1688	27
1	33	0.2063	60
2	31	0.1938	91
3	46	0.2875	137
4	23

Complete the table and determine what percent of the people have exactly zero sibling(s)? %