Whatever system you use, unless you've done a coupon promotion and can simply count the number of coupons redeemed, tracking is the only way you can assess how effectively your advertising is working.

无论使用何种系统，除非您已经做了优惠券促销并可以计算出优惠券的数量，跟踪是评估广告有效性的唯一办法。

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After a few months of trial and error with banner ads and the like, we opted to go with a strict policy that every advertising campaign has a coupon code.

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