Kaom's Way with 20% Fertile Catalyst does not go to 0.5% Life regenerated per Endurance Charge

Creating a Kaom's Way ring and setting the Quality to 20% with Fertile Catalysts leaves the Life regnerated per Endurance Charge at 0.4%, although it should go to 0.5% (I checked on the official Trade website, that this value is indeed reachable).

I also manually edited the Quality value to increase it further. What's strange is that until 24%, the value stays at 0.4% and then it jumps to 0.6% at 25% Quality (this is the point where it would reach an even 0.5% without rounding).

I'm not completely sure what the underlying rounding process should be, but here are some breaking points I found on the official Trade website:

12% Quality --> 0.4% Life regenerated per End. Charge (0.448% unrounded)
13% Quality --> 0.4% Life regenerated per End. Charge (0.452% unrounded)
15% Quality --> 0.4% Life regenerated per End. Charge (0.460% unrounded)
17% Quality --> 0.5% Life regenerated per End. Charge (0.468% unrounded)
20% Quality --> 0.5% Life regenerated per End. Charge (0.480% unrounded)

As you see, 13% should be the breaking point if it is rounded to one significant digit, but for some reason 17% (or 16%, but I could not find that value anywhere) is the breakpoint (all assuming the trade site is correct, can't test this myself atm, though).

ファイル、テスト、エントリーポイントは指定されていません。12–25%前後のFertile Catalystの品質値でKaom's Wayを再現し、その後、Endurance Chargeごとの生命再生のアイテムステータス計算および丸め処理の経路を特定してください。表示されるしきい値が報告されたTradeの値と一致すれば完了です。20%の品質で0.4%ではなく0.5%と表示されることも含まれます。