Multiple Data

I got a question that is stumping me right now.

I have to calculate some simple average and percentile data on salary. I have people who make the same salary, so I can do a straight line calculation of the percentile and average data. The data is presented like this.

<table style="border-collapse: collapse; width: 161px; height: 114px;" border="0" cellpadding="0" cellspacing="0"><col style="width: 48pt;" span="2" width="64"> <tbody><tr style="height: 15pt;" height="20"> <td style="height: 15pt; width: 48pt;" width="64" height="20">Number of People</td> <td style="width: 48pt;" width="64">Salary</td> </tr> <tr style="height: 15pt;" height="20"> <td style="height: 15pt;" align="right" height="20">2</td> <td align="right">10</td> </tr> <tr style="height: 15pt;" height="20"> <td style="height: 15pt;" align="right" height="20">4</td> <td align="right">20</td> </tr> <tr style="height: 15pt;" height="20"> <td style="height: 15pt;" align="right" height="20">6</td> <td align="right">30</td> </tr> </tbody></table>
I could list out the salary manually, but the data is much longer than the above example.

Thanks,
Erik