Errors and Mistakes

[MrDeimos]

The invoker archetype for summoner gets MP based on what spell level they learned and the example it gives is a 5th level summoner has 4 MP but a 5th level summoner gets 3rd level spells
So is that a mistake or?

Not a mistake: 

[color=#ffffff][font=Times New Roman]Diminished Spellcasting: [/font][/color][font=Times New Roman][color=#ffffff]An invoker gains fewer MP than normal equal to the spell level she gains. For example, a summoner of 5th level would only have 4 MP excluding extra MP from Charisma bonus.[/color][/font]

I guess I don't quite understand how to calculate the MP for an Invoker then...