 Hi, this is Dr. Don. I'm back with part 4 of the short video series on a quick start to using pivot tables for business data analysis. You'll recall we created this table using a pivot table. Over here we have the fields and we dragged or drug the various variables, the field names, into locations in order to create this table. And let's say though that your boss is curious. She's looked at your report and she says, I think there's something going on in human resources. I think there may be a difference, a real difference in the salaries between men and women. Now, you look at this and those are pretty big differences, but remember this is a huge organization. FAST has over 300,000 employees worldwide and this is just a large sample. Granted, it's large. It's got over 9,000 records, but it's just a sample. So we cannot just compare these obvious averages. We have to do a statistical test of hypotheses to see if the sample data is sufficiently strong to let us make that kind of conclusion. Your boss says, I'm only interested in full-time employees though. So we're going to go up here. First of all, we're going to click on this drop down, the assignment category, and just select full-time employees to get rid of the part-time employees, which may distort the picture quite a bit. They're generally paid less. So now we've got our data here. Remember this table is not changing the underlying data, which comes from the employee data worksheet here, the 9,200 records. This has never changed when you're working with pivot tables. Now you could go in and select these records using the data tools. There's a sort function and a filter function so you can go through and select records. But then you've got to copy and paste those records into a new worksheet, and it's a chance of error, a chance that you change your original data. It's easier to use pivot table to do that kind of selection for us here. Okay, so now we've got just full-time employees. And if we hover over any data point in the table, we can see what data is underlying that. Here I'm pointing at the average current salary in human resources in Atlanta. It's 81,506, and there's 293 records there that are contributing to that. So if I click in that cell, that is telling Excel that I'm interested in just the records that go to make up this particular piece of data. And if I then double-left click on it, Excel will insert a worksheet which has just those records. And remember I was pointing at here human resources in Atlanta females. So if I look at this set of records there, it's just females in Atlanta in human resources. Pretty neat trick. If I go back here to my pivot table, if I go to a major sub-table, say I click over here on the Atlanta, this is the average of the salaries in those four departments. If I double-left click on that, double-left click, then I will select or get a worksheet that just has those records, just the males, and all four of those departments in Atlanta. Now remember you should rename these worksheets as you go to help you remember what you're getting there. If I go back to my pivot table, again I haven't changed anything. I can go over here to this total and get just those nineteen hundred and seventeen records by double-left clicking. I can go to this total, which is the average of all the males in those offices in those four departments that are full time. Double-left click that, I'll get just those seven hundred ninety five records, and I can go anywhere. If I go to click on Reno, I then would be able to double left click and get just the records, just those rows of data that build up to this seventy six thousand dollar average salary for Reno. So this is a great tool when you're running statistical test hypotheses. For example, if I wanted to test the mean salaries in Reno in those four departments, I could copy out those female salaries, and then the male salaries, and then run my statistical test using those two subsets of the data. So this is a great tool. Learn to use pivot tables. It's really powerful. Hope this helps.