The Capacity Rule Sensitivity report lists all of your capacity rules (that is, Min/Max # Offers Capacity rules and Custom Capacity rules) and their associated sensitivity.
The sensitivity value is the marginal benefit for adding an additional unit of resource, that is, the change in overall score you could expect by increasing the constrained resource by one unit. The unit of resource is defined for capacity rule you create and can be different for each. For example, say you have a Custom Capacity rule that states "The Sum of the CostPerOffer should be <= the value $100,000 for transactions from the offer/offer list Any Offer from channel Any Channel." If the sensitivity is 67, increasing the budget value by one from $100,000 to $100,001 would increase the overall sum of optimized scores by 67. (The meaning of the score is whatever you set it to represent, for example, dollars of profit, dollars of revenue, response probability, and so on.) Similarly, if you create a Min/Max # Offers Capacity rule, the sensitivity would represent the additional score value obtained by increasing the maximum number of offers available by one.
If you create a Min/Max # Offers Capacity rule with a minimum, the sensitivity may be negative. The sensitivity is still determined by increasing the minimum by one, that is, from 100 to 101. Since increasing a minimum constrains the problem even more, increasing the minimum will most likely change the score in a negative way.
You can use this report to analyze the cost of implementing capacity constraints. In an ideal world, there would be no minimum or maximum capacity constraint and your business would use the optimization results, adapting inventory and other resources to maximize the score. The sensitivity value tells you the cost (the amount of score that is lost) by having the maximum capacity rule with its current threshold. With the example of the budget rule, if the sensitivity value were 1,000 where the score represents profitability in dollars, this would mean that spending one additional dollar should return an additional $1,000 of profit. A high sensitivity value should suggest you consider removing or relaxing a maximum capacity constraint. Similarly, a low sensitivity value would indicate that there is low opportunity loss. For example, if the sensitivity value were $0.25, spending an additional dollar to gain 25 cents of profit is likely tolerable.