[Norck]

First of all, you will need a variable to store amount of total tax.
So put it at the top of your gamemode:

pawn Код:

new TotalTaxPaid;

Now you need to update this variable after someone pays some tax.
So your code will looks like:

pawn Код:

new random_money = 1000+random(15000);
    for(new i=GetMaxPlayers()-1; i >=0; i--)
    {
        if(!IsPlayerConnected(i))continue;
        GivePlayerMoney(i,-random_money);
        new string[128];
        TotalTaxPaid +=random_money; // update total tax
        format(string, 100, "You paid %d$ in taxes to finance the State. Total tax pays: $%d", random_money,TotalTaxPaid);
        SendClientMessage(i,COLOR_GREEN, string);

Also, you will need to save TotalTaxPaid if you don't want it to reset after each server's restart.