Coupon Discount limitation

Hi,
I want to limit total discount earned by a coupon. Such that, let I set a discount limit to ?100.

Now let the discount percentage be fixed at 10% on each purchase.
Now suppose,
On 1st purchase customer get ?60 discount on ?600 purchase.
On 2nd purchase customer get ?40 discount on ?400 purchase.

Now we can see the total discount eaened from this coupon is ?100. Now the coupon will expire.

Is it possible any how????

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