Stats of character per level

Dear All, I'm Shomat.
I wanted to know if anyone had answers to calculating the stats of character based on their level.

So far, based on checking few of my characters (Luffy, Zoro, Sanji, Alvida, Buggy), the following worked.

Example: Luffy Gear 2 @ LV17
-----LV1---MAX(LV99)---->LV17
HP:--902---1772---------->1044
ATK:-473---1313---------->610
RCV:-74----227------------>99 (actually 98)

=> For each Stat, calculate the Rate by ((MAXSTAT-LV1STAT)/(MAXLV-LV1)).
    So, for HP, it will be ((1772-902)/(99-1)) = about 8.88 for HP Rate.
=> Then, multiply the Rate * (Current level -1) to get the above; give or take 1 for rounding errors.
    So, for HP, @ LV17, it will be 8.88 * (17-1) = 1044.

Based on Friend's Vivi (Star 4, Nefartari Vivi), it seemed like the above worked. I'm not sure about Vivi Star 5, Princess Vivi...
Thought this may be useful for upcoming Mihawk's battle...

Disclaimer:
I didn't try this out for all the characters, I think it didn't work well for Shanks (Star 4), I'll have to check again.
I would like to know if anyone has figured it out.
Also, I'm sorry about all the "-" in the table. I couldn't remember how to insert Tables in this kind of forum...

Thank you.

It should work for the most part, I used those same equations and it seemed to work for Zoro, Hachi, Alvida, Arlong, Zeff, and a few others give or take a few due to rounding but yea

Thank you for your response Relamir. Hopefully this works for Vivi(☆5), Laboon, Luffy ver2 and such...

I've checked Shanks again. The equation seems to be Polynomial, not Linear...
For those who care, the approximate equation is below.

Shank
HP: 0.0989 * (LV-1)^2 + 5.1513 * (LV-1) + 186
ATK: 0.0680 * (LV-1)^2 + 3.5363 * (LV-1) + 159
RCV: 0.0273 * (LV-1)^2 + 1.386 * (LV-1) + 46

Thanks.