I.e psyduck to golduck each stat increases by 30
Ivysaur->Venusaur Sandshrew->Sandslash Nidoran-female->Nidorina Zubat->Golbat Psyduck->Golduck Mankey->Primeape Abra->Kadabra->Alakazam (As of Gen 6 Alakazam no longer falls under this category) Bellsprout->Weepinbell->Victreebel Geodude->Graveler Ponyta->Rapidash Magnemite->Magneton Seel->Dewgong Krabby->Kingler Koffing->Weezing Staryu->Starmie Dratini->Dragonair Bayleef->Meganium Natu->Xatu Mareep->Flaaffy Lotad->Lombre Whismur->Loudred Vibrava->Flygon Swablu->Altaria Snorunt->Glalie Spheal->Sealeo->Walrein Beldum->Metang Grotle->Torterra Vanillite->Vanillish Deino->Zweilous
As for those Pokemon that evolve in a later generation or have a galarian form, they are not on this list even if their base stats increase by the same amount.