For the article on the company with ticker BPS, see BlackRock Pennsylvania Strategic Municipal Trust (BPS).
A basis point (abreviated as 'bps') is a unit that is equal to 1/100th of 1%, and is often used instead of percentages when discussing interest rates, rates of return, and other percentage-based performance metrics that can occur as fractions of a percent.
1% change = 100 basis points, and 0.01% = 1 basis point.
So, a bond whose yield increases from 5% to 5.5% is said to increase by 50 basis points; or interest rates that have risen 1% are said to have increased by 100 basis points.