CPCs vary depending on the advertising campaign’s objective. If the aim is as simple as gaining post engagement, then CPCs are the least expensive. However, the more complex the objective, the higher the cost-per-click gets. The most expensive is app installs, which means that advertisers need to pay 0.3 U.S. dollars per click that leads to customers installing apps, compared to 0.02 U.S. dollars for post engagement. Brand awareness, page likes, reach and conversions are in the middle of the spectrum. All in all, after a spike in advertising costs in third quarter of 2017, when Facebook CPCs grew by 282 percent year-on-year, the company’s ad rates were being increasingly lowered thanks to their improved targeting and growing engagement.