Other than looking at your T score, you could also look at your bmd value. On average, a healthy person loses 0.25% up to 1% of bone mass per year after bone maturation. For post menopausal women, this loss would accelerate to 1.8% to 2.3% in the spine and 1 - 1.4% in the hip due to the loss of estrogen. You could use this benchmark to compare your annualized rate of bone loss and to see if you had unforeseen faster bone loss.