The hukou statistics derive from the registrations at each administrative level. They include the following items: (1) total number of households; (2) total population of registered permanent residents, including those who have temporarily left their registered residential location; (3) births; (4) deaths; (5) out-migrations and (6) in- migrations (Zhang 1984; Zhang and Wang 1997). The national aggregate statistics count total population with a reference time of 31 December each year.
Two inherited drawbacks affect the statistics. First, unlike other population statistics, this registration system heavily relies upon self-reporting from each household, but whether a household head reports changes in a timely fashion depends upon the incentives from the system. There were considerably different situations before and after the 1980s. Second, the legal registration period within one month could lead to reasonable registration delay. For example, births and deaths occurring in December are very likely to be missed in the current yearly statistics, and included in the next year-end statistics. Certainly, these registration delays could happen every year and cancel each other out. However, one should be cautious when comparing the year- end populations in the hukou statistics with those from other data sources.
Before 1982, the hukou statistics were the only yearly available official demographic source. Generally speaking, the completeness of birth records was good and the statistics could be used ‘sometimes with adjustment and in some cases without adjustment’ (Banister 1987: 17). The 1964 and 1982 censuses reported the completeness of the statistics as 99.2 percent in 1963 and 99.35 percent in 1981 (Zhang and Wang 1997: 88). To some extent this remarkable completeness benefited from the pre-census hukou cleanup program (hukou zhengdun) (hereafter the cleanup program), which aimed to correct accumulated errors in the statistics during the intercensal period (Li 1986). More importantly, it resulted from the extreme importance of the hukou system, and very low population mobility.
Nonetheless, the completeness of the hukou statistics has deteriorated seriously during the past two decades. The 1981 total hukou year-end population was 996.22 million, with only 0.66 million undercounts compared to figures derived from the 1982 census (Zhang 1984). However, compared to the 1990 census, during the period from January 1982 to July 1990 under-registration in the hukou statistics amounted to 20.24 million, on average 2.7 million each year (Zha, Zeng and Guo 1996: 48). The 1990 census provided an opportunity to update the problematic registration system, but during the 1990s, the difference between the hukou registered population and that from other sources became even wider. Since the SSB released the estimated number of total population each year, Table 3.1 shows the comparison of total population between the SSB-estimated and the hukou-registered annual series. If the SSB annual estimates are reliable, this comparison suggests that the under-registration of total population in the hukou statistics amounted to 27.51 million at the end of 2000 (also see Cui 2000).
Table 3.1 Comparison of total population between the SSB and MPS sources in China, 1991- 2000
SSB estimated total population (millions)
Hukou registered total population (millions) Annual difference (millions) Year (1) (2) (3)=(1)-(2) 1991 1, 158.23 1, 145.11 13.12 1992 1, 171.71 1, 155.63 16.08 1993 1, 185.17 1, 165.97 19.20 1994 1, 198.50 1, 176.74 21.76 1995 1, 211.21 1, 187.88 23.33 1996 1, 223.89 1, 198.66 25.23 1997 1, 236.26 1, 209.03 27.23 1998 1, 247.61 1, 218.18 29.43 1999 1, 257.86 1, 228.12 29.74 2000 1, 267.43 1, 239.92 27.51
Sources: The SSB series are from the SSB (2002a); the hukou series are from the MPS (1991-2000). Note: The annual population totals of both series include military personnel.
Prudence is needed to interpret the under-registration of the hukou statistics in the 1990s. First, the SSB official estimates of annual number of births were inflated to varying degrees from year to year. Accordingly, the SSB-estimated number of the total population was also likely to be over-estimated. In this case, the difference between the two sources may not be too wide as shown in Table 3.1. Second, however, there were compensating errors, such as the non-deletion of deaths and non-registration of births, in the hukou statistics. This has been a long-lasting problem since the 1970s. Certainly, at that time, the non-deletion of deaths was the main problem, because many households wanted to keep the benefits associated with the registrations; but the nationwide family planning program, in particular after 1979, also resulted in the non-registration of out-of-plan births (Banister 1987). However, this situation further worsened in the early 1980s, which was closely associated with the introduction of the one-child family planning program and the increasing rural-urban migration, but more importantly, it resulted from the increasingly diminished importance of the hukou system.
The 1982 pre-census cleanup program only reported a compensating error of 0.41 million in the hukou statistics, 0.4 per thousand of the census-recorded population,
but the 1990 cleanup program revealed 34.15 million omissions and 9.63 million duplications, resulting in a net under-registration of 24.52 million people, 2.17 percent of the 1990 census-recorded population (Shen 1994; Zhou 1986). For various reasons, the 2000 cleanup program outcomes were not released, but many national or local news reports during census period presented the picture at different levels. For example, it was reported in Chongqing municipality, that 130,000 deaths remained in the hukou system, while 68, 000 births were not registered (Xinhua News Agency 2000). Such problems commonly existed in other cities. It was reported that 50, 000 decreased persons still had hukou in Wenzhou city of Zhejiang province (Xinmin Evening Newspaper 2000), as did nearly 9, 000 in Wuhan, the capital city of Hubei province (China Youth Daily 2000). It can be expected that the compensating errors at the national level could be even more serious compared to those in the 1980s.
The increasing population mobility greatly affects the completeness and accuracy of the hukou statistics. In China, authorised migrants can change their registration both in residential and in occupational status, while the majority of temporary migrants cannot do so. According to the three most recent censuses, the figures for the temporary migrants with separate current and permanent residence at the county level were 6.58 million in 1982, 21.61 million in 1990 and 78.76 million in 2000 (SSB 1984; SSB 1993; SSB 2002b). This separation between a person and his registered residence is not limited to rural-urban migrants, but also happen with urban residential migrants, especially in big cities in the 1990s (Li 2003). Undoubtedly, this contradicts the basic principle of the system. As a result, the hukou statistics are no longer effective in tracking people’s residence and mobility, as they were before the 1980s.
In most cases, the rural-urban temporary migrants are still included into the statistics at their home villages, their permanent residential locations. However, even in the early 1980s there had been a large number of temporary migrants without registration anywhere. According to the censuses, the figures for people without registration at the census date were 4.76 million in 1982, 8.54 million in 1990, and 8.05 million in 2000 (SSB 1984; SSB 1993; SSB 2002b). It is very likely that the births of these migrants were not registered. According to the 2000 census, more than 30 percent of recorded young migrants aged below 15 had never visited their parents’
home villages, which suggests that even if their parents were still registered in their permanent residence, these children were very likely not registered in the hukou system (Duan and Liang 2004: 57). In general, the hukou statistics have lost their role as effective vital statistics in the wake of rapid socio-economic development. Neither their completeness in registering the total population nor their accuracy in reflecting population distribution has been reliable during the past two decades.