Determine Click-thru Percentage With PHP

I am currently working on a small sponsorship application(PHP/MySql) for my personal blog, and am almost finish, but I am stuck on how to calculate the click-thru rate of my sponsors campaig开发者_运维百科ns.

I was always terrible with working out percentages, so any practical help would be appreciated. The data is stored in the DB as simple numbers.. So as expected, when a page refreshes, or a sponsors ad is clicked, the data updates with an incrementation of 1.

So using these values...say $clicks and $impressions, how would I determine the click-thru rate? What would be the sum I would use to calculate? An example function would really be appreciated.

Kind Regards, Lea

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What you're after is the percentage of $impressions that leads to $clicks. The ratio is found by calculating $clicks/$impressions, and then you can multiply by 100 to see the percentage.

As an example, if there are 100 impressions and 1 click, the ratio will be 1/100 = 0.01, and the percentage will be 0.01 * 100 = 1%.