just create mapping table until max this year

[TSchiefer]

otherwise it is a bit misleading to provide mapping tables that are still subject to change

closes #52

[codecov]

Codecov Report

Merging #53 (8117406) into main (f5158fb) will increase coverage by 0.10%.
The diff coverage is 0.00%.

❗ Current head 8117406 differs from pull request most recent head fa8e7c4. Consider uploading reports for the commit fa8e7c4 to get more accurate results

@@            Coverage Diff             @@
##             main      #53      +/-   ##
==========================================
+ Coverage   71.32%   71.42%   +0.10%     
==========================================
  Files          17       17              
  Lines         701      700       -1     
==========================================
  Hits          500      500              
+ Misses        201      200       -1     

Impacted Files	Coverage Δ
R/write_tables.R	0.00% <0.00%> (ø)

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