Danie Viljoen

Longevity of archived caches: The following graph shows the average age (in days) of archived caches at the time of its last find: (The following cache types were excluded: Event, CITO, L&F, MEGA, Lab.) I was surprised to see how well the Western Cape and Gauteng are doing - I expected the smaller provinces with their lower muggle densities to dominate here.

I am surprised to see that Large is still holding its own - they certainly feel very scarce!

Marion and Prince Edward Islands: I only recently discovered that there are three caches on Marion Island (of which one is archived). The Prince Edward Islands (of which Marion is part), currently listed as part of Antarctica, is actually South African territory, and they fall under Cape Town, administratively. If one includes them, the centroid for Cape Town moves by 2.696km to S33 59.832 E18 31.487

How do you get the Lab caches? I don't see an option in the PQs to get them.

A very interesting way to look at it! I think the reason you don't see the flattening here is because of differing numbers of caches per data point. (You counted the number of caches in a specific year, which for the early years are only a few. The effect of one or two more archived caches in 2001 would be much greater than say in 2016. I counted the number of caches of a specific age. For example, a ten year old cache in my graph could have been placed in any year from 2001 to 2007, depending on when it was archived). I wonder about the anomaly from 2005 to 2006. I guess one will have to look at the specific caches to find the reason. About the total percentage of archived caches - did you ignore CITO, L&F and MEGA events as well?

Cache survival probability: How long does a typical (non-event) South African cache last? The following graph surprised me: What this means is that the attrition rate is more or less constant for the first 11.5 years, at 2.8% per year, much lower than I expected. If a cache can make it to 11.5 years, it tends to become immortal! Up to now only 31% of all South African caches (excluding events) have been archived.

Age distribution of archived caches: The next few postings will be about cache longevity. First, let's look at the age distribution of archived South African caches. (I excluded all types of events.) The average life expectancy of an archived South African cache is 6.6 years, and the median is 6.4 years. The oldest archived cache is GC8FF8 - Paarl Rock Cache, which made it to 14.2 years.

Percentage active caches archived: Lastly, the following graph shows the percentage of active South African caches that are archived each year: (This excludes all events.)

New caches vs. archived caches: The following graph shows the numbers of new and archived caches per year for South Africa: Currently we gain about 2500 caches per year and lose about 1000 for a netto gain of about 1500 per year. (All of these numbers exclude events of all types.) The next graph shows the number of new caches divided by the number of archived caches, per year. The number appears to be stable since about 2009

Number of archived caches over time: This is the same as before, but with events excluded (and the time interval changed to years i.s.o. 6-month intervals): We are currently losing caches at a rate of 2.7 per day, (3.4 if we include events).

True, I did not think of that. I'll rework the numbers to exclude events.

Number of caches archived over time: Yesterday's posting made me wonder about the number of caches that have been archived, especially during the last year. The following graph shows the archived numbers for South Africa in 6-month intervals: Although it may feel as if an unusually high number of caches have been archived during the last few months, the increase (162, or 32%) is not that unusual. The biggest increase in recent times was during the 6 months ending March 2013, when 199 more caches were archived - an increase of 65% over the previous 6 months. I get the impression that the volunteers do not archive dead caches at a steady rate - it tends to build up to big archiving sprees.

South Africa vs. the world: The following graph shows the percentage of all the active caches in the world that are South African: To my surprise we appear to have been gaining on the rest of the world for the last 6 years. The effect of the big (and necessary!) clean-up of dead caches since the second half of last year can clearly be seen.

Active caches per province (This is unfortunately all I have been keeping track of over the years.)

3 Million caches! A major milestone was reached when the 3 millionth (active) cache was published last night. The following graph shows the total number of active caches (worldwide) since 2008: And for South Africa:

Fastest 5000 finds: Only 8 cachers have found 5000 or more caches in Africa: 1. iPajero 834 days 2. GorNat 1429 days 3. rodnjoan 2004 days 4. The Huskies 2080 days 5. TechnoNut 2467 days 6. Louise_Gerhard 2676 days 7. Antron 3187 days 8. cownchicken 3471 days The average and median fastest 5000 finds are both 6.2 years. Fastest 6000 finds: 3 cachers have found 6000 or more caches in Africa: 1. iPajero 1022 days 2. rodnjoan 2784 days 3. The Huskies 3930 days The average fastest 6000 finds is 7.1 years For the major milestones of 7000 finds and up, only iPajero managed to find that many African caches. The following graph shows the find rate of the fastest cacher (iPajero) relative to the runners up: To clarify - this is not really the find rate, it is more a fastest rate per 1000 finds: I simply plotted the fastest time (in days) for every 1000 finds. I find it remarkable that iPajero managed to keep up their find rate through so many years. Every about 8 months another 1000 African caches are found. (And the above does not even include their overseas finds!)

Fastest 3000 finds: 36 cachers have found 3000 or more caches in Africa. The fastest of these were: 1. iPajero 417 days 2. Panters 556 days 3. Spesbona 583 days 4. GorNat 836 days 5. SKATTIE@1 876 days 6. AdieA 933 days 7. ChrisDen 934 days The Huskies 934 days 9. bergbokkie 1044 days 10. JanMich 1111 days 11. TechnoNut 1178 days 12. Porky2 1208 days 13. rodnjoan 1229 days 14. terunkie 1303 days 15. Leon St 1313 days The slowest 3000 finds (Wildbirds) took 3405 days (9.3 years). The average fastest 3000 finds is 4.2 years and the median is 4 years. Fastest 4000 finds: 23 Cachers have found 4000 or more caches in Africa: 1. iPajero 674 days 2. Spesbona 1031 days 3. GorNat 1062 days 4. ChrisDen 1282 days 5. The Huskies 1422 days 6. SKATTIE@1 1569 days 7. rodnjoan 1678 days 8. bergbokkie 1681 days 9. terunkie 1751 days 10. TechnoNut 1790 days 11. PieterM 1916 days 12. Louise_Gerhard 2047 days 13. Leon St 2052 days 14. dolos 2170 days 15. Geelvink 2343 days 16. cownchicken 2387 days 17. Thrips 2398 days 18. Antron 2400 days 19. Henzz 2600 days 20. Wikkelgat 2615 days 21. Danie Viljoen 2635 days 22. HeinG 2816 days 23. Tricky Vicky & Mickey 4910 days The average and median fastest 4000 finds are both 5.6 years.

Highest cache densities: Northern Cape 1km radius: 5 caches around GC3E0DP Oval Track Jan Kemp in Jan Kempdorp 5km radius: 16 caches around GC6K37Q Steam rolled through Kathu 10km radius: 20 caches around GC6AXYT kathu pan

Fastest 2000 finds: 71 cachers have found 2000 or more caches in Africa. The fastest of these were: 1. iPajero 194 days 2. MadSons 303 days 3. Panters 359 days 4. bergbokkie 379 days 5. SKATTIE@1 432 days 6. The Huskies 455 days 7. Spesbona 457 days 8. GorNat 483 days 9. AdieA 560 days 10. ChrisDen 575 days 11. TechnoNut 617 days 12. Geelvink 626 days 13. JanMich 628 days 14. Mixs 661 days 15. rodnjoan 697 days The slowest 2000 finds (sy-chispa) took 2863 days (9.9 years). The average fastest 2000 finds is 3.3 years and the median is 2.9 years.

Highest cache densities: Limpopo 1km radius: 6 caches around GC3QMPY Springbokkie 5km radius: 20 caches around GC143XC The Palm Tree TB Rest Stop 10km radius: 36 caches around GC4N0VW Dalmada tree

Most Favourite Points in the past year It was pointed out to me that I forgot to include the new caches in my article in the latest GoSA newsletter. I hope the following list is correct! The following South African caches received the most new FPs during the year 7 March 2016 to 6 March 2017: 1. GC31WXR Table Mountain Travel Bug Hotel CapeDoc 66 FPs 2. GC5Y00Q Tardis family Behrens 57 FPs 3. GC691EB STAR TREK max beeks 45 FPs 4. GC5BWV4 UP PERISCOPE family Behrens 39 FPs 5. GC6K7A4 Red or Blue family Behrens 39 FPs 6. GC5D3BX The Vault Henzz 38 FPs 7. GC548HP Intersect 2.0 family Behrens 32 FPs 8. GC6K78M Governor's Ghost WC Geocachers. 31 FPs 9. GC6RJGA Minecraft Hero WC Geocachers. 31 FPs 10. GC60190 Signal the frog books his Licence family Behrens 28 FPs

Highest cache densities: North West 1km radius: 12 caches around GC184GP Longdrop 5km radius: 56 caches around GC5VNC3 Railway-channel 10km radius: 74 caches around GC5BA1Y VA52 Densest 1km radius Densest 5km and 10km radius

Fastest 1000 finds: 236 cachers have found 1000 or more caches in Africa. (Unfortunately I do not have the data for overseas finds.) The fastest of these were: 1. iPajero: 20 days 2. Spesbona: 40 days 3. MadSons: 93 days 4. tjoklits: 113 days 5. Panters: 125 days 6. Happy Hunters SA: 130 days 7. The Huskies: 145 days 8. bergbokkie: 157 days 9. GorNat: 167 days 10. SKATTIE@1: 168 days 11. B and C Inc: 174 days 12. Wazat: 182 days 13. JanMich: 186 days 14. Thedivespot: 189 days 15. Leon St: 190 days At the other end of the spectrum, Nish4 took 3605 days (9.9 years!) to get to 1000 finds! The average fastest 1000 finds is 2.3 years and the median is 1.8 years.

Highest cache densities: Free State 1km radius: 25 caches around GC3F8Y7 Naval Hill Nr.3 5km radius: 167 caches around GC3711R Hopwood Playground 10km radius: 244 caches around GC3FNZD LHP from the hill (yellow = 10km radius, orange = 5km, red = 1km)

Highest cache densities: Mpumalanga 1km radius: 18 caches around GC21QAX Way to Go.... 5km radius: 99 caches around GC6DGW1 Parking with a view 10km radius: 139 caches around GC23P1J We Wonder.... (yellow = 10km radius, orange = 5km radius, red = 1km radius)