How it's worked out
Conversion rate = results / attempts x 100. Pick two steps and a period, count how many reached the first step, and count how many of those reached the second. 12 deals from 60 meetings is 12 / 60, so 20%, or 1 in 5 as a ratio.
The ratio and the rate are the same number written two ways. The rate is easier to compare. The ratio is easier to plan a week with, because it tells you how many of something to do.
One rate from first call to signed deal hides where the problem is, so break it into steps.
Worked example, with made-up figures: this month you made 400 calls, had 80 conversations, booked 20 meetings and closed 4 deals. Calls to conversations is 1 in 5, conversations to meetings is 1 in 4, and meetings to deals is 1 in 5. Calls to deals is 1 in 100, so each deal took 100 calls.
Now work back. For 6 deals next month you need 30 meetings, 120 conversations and 600 calls, about 30 calls a working day. Move meetings to deals from 1 in 5 to 1 in 4 and it's 24 meetings, 96 conversations and 480 calls.
Count each step in the same period, and give a slow step time to finish. Deals closed this month often come from meetings held last month.
Where it shows up in your week
A ratio only helps once it's a daily number. The activity calculator works back from your goal to the calls, conversations and meetings each week needs, from your own conversion rates.