Taiwan's country-level data is often missing from the international organization's dataset, notably World Development Indicators, due to political reasons.
To obtain the "country"-level times-series data for Taiwan, visit the official website of Director-General of Budget, Accounting and Statistics, Executive Yuan, Republic of China. For basic statistics, click "Statistical Yearbook" on the right, then you can download data since 1975 in PDF files. For earlier years, look for Statistical Yearbook of the Republic of China in your university library. See also WDI's FAQ on Taiwan.
Notes on life expectancy data in Statistical Yearbook of the Republic of China:
Life expectancy data for years 1972-1977 was revised in the 1982 issue and has been unchanged since then.
Life expectancy data for years 1957-1971 was revised in the 1987 issue and has been unchanged since then. The earliest year available in the 1987 issue is 1957. Therefore, data for years before 1957 in the earlier issues may not be reliable.
Notes on school enrollment rates data in Statistical Yearbook of the Republic of China:
Enrollment rates data first appears in the 1989 issue for years 1977-1988. Data for 1976 is added in the 1990 issue and last appears in the 1994 issue. Data for 1989 is revised in the 1991 issue. Data for 1988 and 1990 is revised in the 1992 issue.