How can advertising efficiency be measured?

How can advertising efficiency be measured?

Managers can keep track of their advertising efficiency in the following areas:

a.Advertising costs incurred per hundred target customers .

b.The percentage of audience who viewed or noticed or associated and read the advertisement or listened to it (depending upon the medium)

c.Opinions of the consumers on the advertisement : how they found it. Obtaining their feedback whether positive or negative.

d.Purchase response of the consumers after coming across the ad.

e. Inquiries generated by the add: (how many and how frequent).