kˈɑːmənli jˈuːzd vˈæljuːz fɔːɹ ɑːɹ tˈɪldə fˈaɪv ɔːɹ ɡɹˈeɪɾɚ, ɔːlðˈoʊ mˈoːɹ pɹɪsˈaɪs vˈæljuːz ɑːɹ jˈuːʒuːəli əbtˈeɪnd baɪ fˈɪɾɪŋ ʌv tˈɛnsəl ɔːɹ kəmpɹˈɛsɪv ɛkspˌɛɹɪmˈɛntəl dˈeɪɾə.
Commonly used values for  are ~5 or greater, although more precise values are usually obtained by fitting of tensile (or compressive) experimental data.