hˈʌlʔn̩ nˈaɪntiːnhˈʌndɹɪd sˈɛvənti ˈeɪt jˈuːzd "əbzˈɜːvd ɛkspˈɛndɪtʃɚ ʃˈɛɹz" æz wˈeɪts, ænd ɪn ðæt mˈɑːdəl "ðə fˈɜːstˈɔːɹdɚɹ ˈɪmpækt ˌɔn ˈaʊtpʊt əvə tˌiːˌɛfpˈiː ʃˈɑːk tʊ ɐ fˈɜːm ɔːɹ ɐn ˈɪndʌstɹi ɪz ˈiːkwəl tə ðæt ˈɪndʌstɹi ɔːɹ fˈɜːmz sˈeɪlz æz ɐ ʃˈɛɹ ʌv ˈaʊtpʊt."
Hulten (1978) used "observed expenditure shares" as weights, and in that model "the first-order impact on output of a TFP shock to a firm or an industry is equal to that industry or firm’s sales as a share of output."