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The Mailroom / The numbers
Every figure in one place

The numbers: every figure on this desk in one place

Every count, ratio and duration used anywhere on this site, with the sample it comes from and the arithmetic it rests on, so a reader can check the desk’s claims instead of taking them.

Desk spec
tallies
11
samples
10
pages
18
figures
all re-derivable
the five kindsA receipt records something that already happened, marketing promotes something, a service note explains a state of the account, a security alert says something changed, and a legal notice is the message whose arrival is itself a step.
the two switchesOne stops marketing and nothing else - 12 of 50 messages on the samples. The other does not stop anything: it changes the channel the remaining 38 travel on, which changes how they arrive and what they prove.
the three countsSent is what the operator's log holds (50 of 50), arrived is what a delivery receipt shows (48 of 50), and read is what a read receipt shows (21 of 50). Three counts, routinely called one.
Direct answer

One account receives fifty messages in thirty days, of which twelve are marketing and thirty-eight are not. Eight kinds of message cross five channels in a grid of forty cells, twenty-four of them permitted. Delivery takes 0.9 seconds by email and 2 days 6 hours by post. Fifty messages are sent, forty-eight arrive with evidence and twenty-one are read. The month costs 1.3352.

50messages in thirty days (sample A)
12of them marketing, the only switchable kind
76.0%of the volume an opt-out cannot reach
24 of 40grid cells permitted (sample C)
0.9 semail arrival (sample D)
216,000times slower by post
48 of 50messages with arrival evidence (sample F)
21 of 50messages with read evidence
1.3352the month per account (sample H)
9 of 12log fields kept (sample E)
2 of 4notice windows that survive the post (sample I)

The month, three ways

sample A - by kind receipts 30 (60.0%) + marketing 12 (24.0%) + service notes 4 (8.0%) + alerts 2 (4.0%) + notices 2 (4.0%) = 50 = 100.0% a day on average = 50 / 30 = 1.67 messages switchable = 12 / 50 = 24.0%; unswitchable = 38 / 50 = 76.0% ratio unswitchable to switchable = 38 / 12 = 3.17 to 1
sample C - by channel email 33 + in-app 9 + push 4 + SMS 2 + post 2 = 50 grid: 8 kinds x 5 channels = 40 cells, 24 permitted = 60.0%, 16 refused = 40.0%; one mandatory channel per kind
sample D - by time email 0.9 s; in-app 0.0 s; push 1.2 s; SMS 3.4 s; post 2 d 6 h 2 d 6 h = 194,400 s; 194,400 / 0.9 = 216,000 sent -> delivered 0.9 s; delivered -> read 2,481 s = 41 m 21 s; read -> acted 1,778 s = 29 m 38 s; reader / carrier = 2,757

The message, followed to the end

sample F - four moments sent 50 (100.0%) -> delivered 48 (96.0%) -> read 21 (42.0%) -> acted on 14 (28.0%) of the 48 that arrived, 21 were read = 43.8% post: 2 messages, arrival evidence 0 of 2, read 0 of 2
sample G - the address 2 addresses of record; a change takes 24 h messages a day = 50 / 30 = 1.67; caught in the window = 1.7 marketing caught = 12 / 30 = 0.4
sample H - the cost 33 x 0.0004 + 9 x 0 + 4 x 0 + 2 x 0.0410 + 2 x 0.6200 = 1.3352 per year = 16.0224; per message = 1.3352 / 50 = 0.0267 all fifty by post = 31.0000 = 23.2 times the mixed month 4 messages (8.0%) carry 1.3220 of 1.3352 = 99.0% of the cost

What is not in these figures

Every number above comes from the eight samples plus the two defined on their own pages. Nothing is observed from a company, and no real operator, platform or person is described by any of it.

The arithmetic is shown in full so each figure can be re-derived. Where a figure is a ratio of two other figures on this page, both are printed beside it.