How important it is to calculate working capital turnover ratio of a company and why it is different for industry to industry?

It is a good analysis tool.
Failure to establish relationship between two accounting elements (sales and operations) can be could effect efficiency.
Businesses  that only sell services, do not need to pay cash for inventory or can convert goods into sales quickly will need lower level of working capital.
In those cases, this ratio will be higher.
Hence an industry matters in determining the optimum level of ratio for which a useful comparision can be made.

there are alot of benefit for caculate the working capital ,because this measuring will let the company knows the perecntage of the profit that will come back to the item of working cabital ,what I mean this ration will let you know ,the channel of spend your prfit ,may you spend your profit wrong way "by fixed assets and this is not help you to get the target of company " that is mean this ration will help you also for evaulate the managment dession of the company

in some companies, it's confidential

this ratio is calculated by  devide the net profit on working capital and it indicate to ffectiveness in using working capital

The working capital turnover ratio is also referred to as net sales to working capital. It indicates a company's effectiveness in using its working capital.

 

The working capital turnover ratio is calculated as follows: net annual sales divided by the average amount of working capital during the same month period.

 

For example, if a company's net sales for a recent year were $2,, and its average amount of working capital during the year was $,, its working capital turnover ratio was6 ($2,, divided by $,).

 

Working capital is defined as the total amount of current assets minus the total amount of current liabilities. As indicated above, you should use the average amount of working capital for the year of the net sales.

 

As with most financial ratios, you should compare the working capital turnover ratio to other companies in the same industry and to the same company's past and planned working capital turnover ratio.