We check PSA 10 sales data every day for the Japanese cards we track. Each chart below shows the monthly average PSA 10 sold price, the PSA 10 rate and the number of PSA 10s, all from official PSA data.
Still climbing
These rose every month from August to October.
Leafeon LV.X · Dawn Dash

August $2,259 → September $2,675 → October $5,375 (+138% since August).
Clefairy 1st Edition · Expedition Base Set 028/128

August $248 → September $425 → October $442 (+79% since August).
Yanmega 1st Edition · Clash at the Summit 006/080

August $631 → September $916 → October $945 (+50% since August).
Houndoom 1st Edition · Reviving Legends 043/080

August $331 → September $392 → October $485 (+46% since August).
Dratini 1st Edition · Expedition Base Set 031/128

August $238 → September $256 → October $325 (+36% since August).
Machamp 1st Edition · Clash at the Summit 045/080

August $869 → September $1,154 → October $1,176 (+35% since August).
Bouncing back
These dipped in September and picked up again in October.
Krookodile UR 1st Edition · Ryuno Blade 055/050

August $1,198 → September $786 → October $1,048 (+33% since September).
Tyranitar 1st Edition · Reviving Legends 044/080

August $2,296 → September $2,233 → October $2,812 (+26% since September).
Meganium 1st Edition · SoulSilver Collection 009/070

August $692 → September $676 → October $733 (+8% since September).
Sliding
These fell every month. If one is on your list, it now sells for less than it did in August.
Blastoise EX SR 1st Edition · 20th Anniversary 092/087

August $2,531 → September $2,187 → October $1,784 (-30% since August).
Holding steady
These barely moved from August to October.
Venusaur & Snivy GX SA · Remix Bout 066/064

August $274 → September $271 → October $261 (-4% since August).
Donphan 1st Edition · HeartGold Collection 046/070

August $543 → September $690 → October $661 (+22% since August).
Monthly average of PSA 10 sales. October = through October 21. Source: PSA. Past prices do not guarantee future prices.
We also post a weekly version on Instagram at @jpretrogamestore.