How many times should you call the prospects in a Phonathon pool before giving up on that group? Five? Ten? 50? If you segment based on propensity to give, looking at your call results will give you the right answer. If you segment by other criteria, there is no right answer: You’ll make too many AND too few call attempts to those prospects — simultaneously.
Bear with me and I will try to explain.
This past summer, I proposed a new way to approach Phonathon segmentation. My top-level sort would be the propensity-to-give scores I came up with from my Phonathon-specific predictive model. I didn’t completely do away with the more “traditional” segmentation criteria (eg., faculty and past giving status), but they had lower priority. (See Applying predictive modeling to Phonathon segmentation, 28 July 2010.)
So, how’s that working? We’re just past the middle of the term, so obviously no final verdict is in, but so far the results are looking favourable for the model-driven approach. I’ll have more to say about that in the coming weeks. Today I want to zero in on one particularly interesting aspect of Phonathon: The efficacy of multiple call attempts, and the crucial role predictive scores play in choosing the optimal amount of effort to expend.
In my segmentation plan, alumni with the highest scores get called first and most often. This is important. Ask any phonathon manager and they’ll tell you the biggest challenge right now is getting people to answer their phones. Regardless of a prospect’s score, between 60% and 65% of calls are going to answering machines. We have some talented fundraisers in the room; odds are good that if one of them can get you on the phone, you’re going to give! But they have to get you on the phone first, and that is proving incredibly challenging.
Given that barrier, it makes sense that we would want to call our best and most likely givers early and often. Many will never answer their phones, but the hope is that enough of them will answer to make many repeated attempts worth the time and expense.
Have a look at the chart below. This shows the number of “Yes” pledges (i.e., with specified dollar amounts) that have come in on the first, second, third …. up to the ninth call attempt. Each coloured bar represents prospects with a certain decile score from the predictive model (with 10 being the highest decile). So far only one person has picked up the phone the ninth time we called him or her, and made a pledge — and that person, no surprise, is in the highest decile.
Pledge numbers drop dramatically as the number of call attempts increases, even for the 10s — but a quick glance shows that the 10s consistently give twice as often as the next decile down. Much below decile 8, and calling more than a handful of times seems to be a lost cause.
Let me anticipate an objection and say, yes, I know: We have spent far more time on the 9s and 10s than we have the lower score deciles, therefore the lower scoring alumni are showing up with fewer call attempts and fewer pledges. Let’s look at it a different way, then. Let’s include the “Nos” as well as the “Yeses”. Then we can see what percentage of decisions went in our favour at each call-attempt stage and each score decile. (For simplicity’s sake I will leave out the “maybes” and other results that are not really a decision.)
To start off, here’s a summary of how all Yes AND No prospects to date break down by number of call attempts.
The number of decisions falls off sharply with each additional attempt — by about half, in fact. With each additional call attempt, it is that much less likely that you’ll get the prospect on the line. That’s the nature of the beast.
That’s the bad news, but here’s something interesting. The percentage of “Yes” responses starts relatively low with the prospects who answer on the first attempt, but seems to go UP slightly with the number of attempts it takes to get a decision! See this chart:
I wouldn’t have expected to see that, but it does go to show that multiple callbacks can pay off. Not for all prospects, though! I will show in a moment that the steady or increasing pledge percentage is due to the activity of a select group of prospects.
Before we continue: I wouldn’t pay too much attention to the bars for the seventh attempt and higher. These represent small numbers of prospects, and I don’t trust the percentages. Therefore for the sake of simplicity, let’s focus on prospects who made decisions at attempts numbered 1 through 6 only. For the same reason, let’s focus on score deciles 6 and up, because while 161 prospects at score level 6 have made decisions so far, only five prospects at score level 5 have done so — that’s not enough data to make valid conclusions.
Okay … I know the next chart looks confusing, but stay with me: This one really brings it all together. Have a look, then read my discussion below.
Start over on the left-hand side, with the group of bars that shows how people who made a decision on the first call attempt break down by decile score. The 10s outshine everyone else, while everyone with a score of 6 through 9 are all neck-and-neck with regards to percentage of Yes decisions.
Now move right, to the next group of bars which represent people who made a decision at call attempt number two. The 10s are holding their own, and some of the other score levels are improving their pledge percentages. After three call attempts, though, the lower score levels mostly fall away, while the 10s keep improving as a percentage of decisions made. The numbers at the 6th attempt are small — only 32 Score 10s said yes on the 6th call (out of 61 decisions) — but the trend is pretty encouraging, no?
Does it not seem worthwhile to keep calling our highest scorers for a while yet? With more calling and more data, it should become clear when a reasonable cutoff for each score decile has been reached, but we have a ways to go yet.
How do you currently decide when a calling pool is exhausted? When the contact rate falls below some level that you consider acceptable? When the dollars per employee hour are too low? Or simply when the calling room seems a little too quiet?
Well, in my calling room we are going to have some rather quiet nights in the coming weeks. Contact rates do drop rapidly as pools are called repeatedly. But I know now that pledge rates for the highest-scoring alumni are good enough to justify a little bit of boredom on the part of callers, because nightly totals remain respectable as long as we focus on the best prospects.
The bottom line: Keep on calling, but only if you’re calling the right people.
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