In hindsight, it is possible to discover errors in TAI and to make better estimates of the true proper time scale.
ɪn hˈaɪndsaɪt, ɪɾ ɪz pˈɑːsᵻbəl tə dɪskˈʌvɚɹ ˈɛɹɚz ɪn tˌiːˌeɪˈaɪ ænd tə mˌeɪk bˈɛɾɚɹ ˈɛstᵻməts ʌvðə tɹˈuː pɹˈɑːpɚ tˈaɪm skˈeɪl.