npe on simple type usage

[Ken in Nashua]

Folks,

I keep getting NPE on simple calculations.

Is there something here that tapestry doesnt like ?

    public Float getPpa() {
        Float result = new Float(getPts() > 0 ? getGp() / getPts() : 0);
        return result;
    }

    @PropertyDescriptor(nonVisual = false)
    public Float getPpg() {
        Float result = new Float(getPts() > 0 ? getGp() / getPts() : 0);
        return result;
    }

both these routines are causing NPE.

getPts() getGp() and getPts all return Integer.

?