The reason behind IPv6 adoption rate dramatical drop in China according to Google measurements?

Google has an IPv6 measurement page that reports that their numbers report on the percentage of users that access Google over IPv6.

According to the report by Jan 2020 0.3% of users in China used IPv6 to access Google

However, looking at this metric in dynamic we see the substantial drop starting from June 2019. enter image description here

I failed to find any solid news that may cause such behavior. I have two hypotheses in mind.

  1. Also as it is a percentage metric, they can adjust their calculation on the total internet penetration rate in China.
  2. Previously open discussions between netizens took place on Google Plus groups. In April 2019, Google shut down Google Plus. Technical discussions continue on Chinese-language blogs, forums, and groups. For obvious reasons, discussions must be hosted outside China, and posters must register under pseudonyms. So probably that caused the shift from Google services but I hardly believe that it may cause such plummet.

Three-dimentional measurements

I’m totally OK with regular grid and counting squares for purposes of movement, spell and weapon targeting, and determining areas of effect. Area shapes neatly match with measurements made square-by-square, so I may construct any irregular shape if needed, including things like spreads.

What I can’t find rules for is how to count above things in three dimensions (including ‘double-diagonals’).

If I understand correctly, at least first diagonal should be ‘free’ on both axes for far edges of areas to be consistent (for effects and weapons to affect things on those edges), but is there some rule for how to count squares after the first, and if there isn’t one, how you suggest to handle this?

For example, how would you build 20′ radius sphere originating from a point, situated 20′ above the ground? For simplicity, you may provide four pictures, showing areas affected 0′-5′ above the ground (this one would be 10′ square), 5′-10′ above, 10′-15′ above, and 15′-20′ above (this one would be regular 20′ radius circle).

As a note, for now I handle this mostly by looking, what radius circle would a sphere share with a plane, situated on a given height, and then use this radius as a ‘new’ area of effect for those on this height. But it doesn’t seem to always produce right results. In my example above, this method would result in second and third layers to be identical, which is probably incorrect.

Also, I play mostly by post, so time is not an issue.

Baseline measurements [on hold]

I need to compare 2 different results to determine best performance (best defined as lowest).

Baseline measure is set for each level for expected performance.

Baseline measure for each level increases as level increases but at diminishing rate.

So as an example:

Person A averages 100.4 with an average level of 4.3

Person B averages 89.6 with an average level of 6.8

Who performed better given the following info:

table with level and baseline measurement

In Excel; graph with standard deviation etc. for many measurements of many series?

Let’s say I have an Excel-file with 100 measurements for each N and each measurement has its own result k as follows:

N        k 10       32 10       38 10       25 ...      ... 100      260 100      308 100      295 ...      ... ...      ... ...      ... 500000   1231423 500000   1335471 

I want to make a graph in Excel that shows each value of N as x-axis and with k’ as y-axis but k’ being the mean, standard deviation and median etc. of the 100 measurements for each N.

Is this possible? Thank you!