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Attack Natures:

Adamant (Special Attack rises slower), Brave (Speed rises slower),
Lonely (Defense rises slower) Naughty (Special Defense rises slower)

Special Attack Natures:

Modest (Attack rises slower), Quiet (Speed rises slower),
Mild (Defense rises slower), Rash (Special Defense rises slower)

Defense Natures:

Bold (Attack rises slower), Impish (Special Attack rises slower),
Relaxed (Speed rises slower), Lax (Special Defense rises slower).

Special Defense Natures:

Calm (Attack rises slower), Careful (Special Attack rises slower),
Sassy (Speed rises slower), Gentle (Defense rises slower).

Speed Natures:

Jolly (Special Attack rises slower), Timid (Attack rises slower),
Hasty (Defense rises slower), Naive (Special Defense rises slower).

Except you forgot Hardy, Docile, Bashful, Quirky, and Serious natures are neutral. And the nature bonuses aren't raising slower. they raise the score by 10% of the base. and the one that get's "slowed" is really just a -10% of the base. It's not increasing it's stat slower. it's stat is increasing at the same speed, but it removes 10%, making it appear smaller, not slower.

Use this one. (All scores refer to a 10% change, and when a score increases by 10% and then decreases by 10% of the base, it's a change of 0%, for simple math.)
Attack +
Hardy (-Attack)
Lonely (-Defense)
Adamant (-Special Attack)
Naughty (-Special Defense)
Brave (-Speed)

Defense+
Bold (-Attack)
Docile (-Defense)
Impish (-Special Attack)
Lax (-Special Defense)
Relaxed (-Speed)

Special attack+
Modest (-Attack)
Mild (-Defense)
Bashful (-Special attack)
Rash (-Special Defense)
Quiet (-Speed)

Special Defense+
Calm (-Attack)
Gentle (-Defense)
Careful (-Special Attack)
Quirky (-Special Defense)
Sassy (-Speed)

Speed+
Timid (-Attack)
Hasty (-Defense)
Jolly (-Special attack)
Naive (-Special Defense)
Serious (-Speed)
Here's an example.
A level 100 Arceus (for it's uniform stats) with straight perfect IV points, and no EV points, will have Attack, Defense, Special attack, Special Defense, and Speed of 276 across the board.
If you have a Timid nature, you end up with an attack of 248, and speed of 303. The rest of the stats remain the same. Now, if you take 276, move the decimal place over 1. then subtract 276 with the new number you get 248.4, Which, rounded down is the number that the decreased stat is. Likewise the Speed would increase by the same amount from the base, 303.6, always rounding down. the same holds true for every other pokemon, and for every other nature. It's important to know what the nature raises, but it's just as important to know what the nature decreases. A Rampardos is a good beefy pokemon, with amazingly high attack, but it is also important what it will decrease. and how much so you can compensate with any EV training you might want.