When netting is attached to lines, it should be longer than the lines so as to have a proper looseness.
This excess length is expressed as a percentage of the stretched netting. This is the hanging ratio.
The formula for figuring the hanging ratio is: stretched length of netting minus length of netting, divided by length of netting.
Ratio % = (str length of netting less rope length)/str length of netting)
The shape of mesh is greatly influenced by the hanging ratio.
Multiply the stretch mesh size times the number of mesh deep times the % height to get the total height of net.
Multiply the stretch mesh size times the number of mesh long times the % length to get the total length of net.

The following shows the heights and lengths of the mesh for different hanging ratios.

For sports nets such as batting cages and backstops, it is best if the mesh is close to the same height and length with a ratio of 29.3%.
If possible hanging ratio should be between 25% and 35%.
Seines are normally hung as close as possible to 1/3 which is a hanging ratio of 33.3%. If possible hanging ratio should be between 20% and 40%.
Gilling type nets are normally hung between 1/2 and 2/3 which is a hanging ratio of 50% to 66.7%. Generally more is better, but over 70% will start to become too dark in the water.