what is the governor limit in epcmcs for allocation rules

Summary: Hi All, was trying to run one rule but I am getting the error as below:

Warning: Rule cannot be saved because it failed the following validations: Potential Source Count 39,847,939,691,844,723,750,000 is exceeding the Upper Limit 15,000,000,000,000,000,000,000.

is there any document which gives the threshold value for this

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