Percentage signs can be used to show that sections immediately before a bar of music are played again. A single percentage sign means play the bar before again. So in the example below the same bar of music would be played twice.
When two diagonal slashes are shown in a percentage sign filling two bars, this means play the two bars before again. Sometimes a '2' is written above to add extra clarification. In the example below the third and fourth bar will be the same as the first and second.
There is also a four bar version of this but it is very rarely used in drumscore.com notation. In this case there are four diagonal slashes in a percentage sign that is in the middle of four bars. Again a '4' is sometimes put above to clarify. In the example below bars 5 - 8 are the same as bars 1 - 4.
