Hi 4thDan,
The points you receive or lose depend on your opponent's rating. 

If you beat someone with a higher score than you, you'll get more points than
if you beat someone with a lower score. 
And if you lose to someone who has less points than you,
you will lose more points than if you had played against a stronger player.

For more information have a look at FlyOrDie's rating table:  

https://www.flyordie.com/games/help/rating_system.html

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Players with a new nickname have the ≈  sign (approximately equal) by their score. 
This  ≈ sign indicates that this person has played less than 20 games, therefore their rating is "provisional". 
After the 20th game, the sign will be removed.

Ratings are calculated differently when you play against these players. The rating adjustment will be less.

If your opponent has never played a game before (denoted by ---) the rating change will be half of the normal.
If your opponent has only played 10 games, the rating change will be 3/4 of the normal.
And if your opponent has played 20 games, the rating change will be normal.

Kind regards,
John