 It is quite obvious that not all hits are equal. You would rather hit a home run than a single or a double. So with that element of power in mind we have the statistic of slugging percentage. Although kind of like on base percentage it's technically an average more than a percentage. And what it is an average of is the average number of bases reached per bat. And when we refer to bases here we are only referencing bases reached due to hits. Singles doubles triples home runs. So if better is hit by a pitch that does not count toward his slugging percentage. So the first thing we have to do is find his total bases. And since we just said that this is only bases reached due to hits we take his number of singles plus two times his number of doubles because he's gaining two bases for each double plus three times his triples plus four times the number of home runs he has. Add those four numbers up and we've got total bases. Websites usually specifically list how many hits, doubles, triples and home runs a player has. But rarely do they list singles in its own category. So what you can do is add up his number of extra base hits, subtract that from his total hits and the answer will be his number of singles and then we plug all those numbers into the total bases formula. So now that we've got our total bases we can divide that by our players number of at bats and Bob's your uncle we've got our slugging percentage. So this is a little bit different than batting average or OBP because if a hitter were to come up his first at bat and hit a home run his slugging percentage would be four over one which is of course four. Again average number of bases per at bat which means our scale for what is good or poor slugging value is going to be way different. Really good slugging percentage is going to be somewhere on the higher five or six hundreds. But the best hitters are still not getting hits about 70% of their at bats so nobody will have a slugging percentage over one for a whole season. Average slugging is somewhere in the low five hundreds of the four hundreds under four hundred and you're starting to lack power. Unlike average OBP though a low slugging percentage doesn't necessarily mean a bad thing. It just means you aren't getting a lot of extra base hits. Each row would probably be a good example of this type of player. He is slugging at a rate of 419 for his career which is right around the league average but he's got an OBP of 365 when the league average is somewhere in the 330s so overall he's a much better than average player despite what his slugging percentage would tell you. Speaking of each row let's use his 2004 season for an example. He had 704 at bats 262 hits 24 doubles five triples eight home runs. So before we get to total bases let's figure out his singles so 262 minus 24 minus five minus eight that's 225 singles. So then we'll plug that into the formula 225 plus two doubles times two plus three times five triples plus four times eight home runs all that equals 320 total bases so divided by 704 bats gives us 455 so this was actually a pretty good year for each row considering the league average slugging percentage in 2004 was 428. Now that we know what slugging percentage is we can very easily use it to calculate another very common stat that you'll hear which is called on base plus slugging or OPS for short and it is exactly what it sounds like OPS equals on base percentage plus slugging percentage. The idea behind OPS is that we're taking two skills getting on base and power and combining them into one stat and knowing how we calculate both of these is probably fair to say this is kind of a crude stat because you're adding together two numbers that are calculated in completely different ways that have different scales of what is good and bad and one is probably more important than the other but as far as an OPS scale goes we are looking at anything over 900 being pretty great 700s are probably average and below 650 you're getting weaker. I won't do a whole example but since we just found each row's slugging percentage from 2004 was 455 his OPS that year was 869 so his on base plus slugging is split fairly evenly between his on base percentage and his slugging but as we just saw this will not always be the case for power hitters especially who have a slugging percentage upwards of six or seven hundred. Whenever you're evaluating a player it's best to look at every stat that you can because the more stats that you know and the more you know how each of these stats relate to each other will give you a much better picture of what type of player you are looking at than just one or two numbers.