Ad Campaign Managing Strategies: Tunnel Strategy ~2 min
In essence, it requires two sets of values: the floor and cap for Cost per Result (like click, install or another action), and the upper and lower bid limit at Facebook Ad Auction.
In order to implement this strategy, you need to have a clear picture of what your goal is, what results you are looking to get, and how much you are willing to pay for each result, together with the maximum value of your bid and your total budget. Your bid will be changing within the set boundaries at set intervals (for instance, 2 cents), helping you to achieve the most results at a lower cost.
Let's take an App Installs campaign. We want the CPI to remain within the desired range. In the following image you can see Ruleset 1 and Ruleset 2 limiting the maximum and minimum cost per install. The Actions section sets bidding boundaries and the up/down interval value.
Ruleset 3 is designed for cases when there aren’t enough results, raising the bid to increase the number of installs.
There is an alternative to setting bid limits - you can set the campaign budget range instead. This way your daily budget value will be decreasing and increasing within the set corridor.
Ruleset 1 and Ruleset 2 set the same CPI range as in the first example, while Actions regulate the lower and upper Budget limits and its change interval.
Ruleset 3 is also set to raise the bid to gather more installs if there aren't enough.