Close() parameters

Can someone explain to me exactly what the second parameter does in the Close() function?
I’ve read through the online help but it made no sense to this simple man.
In this example, why is the close price different when I use #Sector as a param?


We have created sector, subsector, industry, and subindustry benchmarks as discrete time series. You can actually see them if you go to the multi chart and choose from RBICS. We’ve carefully aggregated the performance of each of these groups of companies using cap-weighted trimmed averages. So Close(0,#Sector) will get you the closing price of that particular sector benchmark. So if you want to compare the 10-day return of a company to that of its sector, you can compare Close(0)/Close(10) to Close(0,#Sector)/Close(10,#Sector).

So by using the second parameter, Close() no longer has anything to do with the stock being looked at, but rather that stock’s sector average?

That’s correct.