The term cost basis (also called tax basis) refers to the calculation of the original cost of obtaining your stock shares. Your original cost basis is needed when determining whether to report a capital gain or capital loss on the sale of your shares.
In order to determine your cost basis, you will need to review your original purchase records. If you purchased the stock through a broker, you may be able to obtain this information from the brokerage firm. If you participated in the Investor Services Program, the purchase information would be reflected in the account statements you received from Computershare.
The following resources may be helpful to you when attempting to calculate your cost basis:
PPG Stock Split History & PPG Dividend History
Closing Stock Price by Quarter End
Individual situations vary greatly based on your specific financial situation. We recommend you contact your accountant or tax advisor for the latest reporting guidelines appropriate to you. You may also visit the IRS web site for additional information on calculating cost basis.