STATE AND LOCAL INDEBTEDNESS 59 as 509 of the state and local total, although in 1926 they amounted to a larger percentage of the total than did those of any one of the three groups of local governments. The total annual bond issues of state and local govern- ments are subject to considerable variation. State bonds have not been issued in uniform amounts, and the variation in local bond issues is very marked. Market conditions probably account for a part of the variation. In general, however, the relation between bonds issued and market factors is not particularly close, for the reason that govern- mental needs cannot always be adjusted to obtain the maxi- mum advantage from favorable market conditions. While the total for bonds issued in any year or over a period of years is significant, the purposes of issue are of even greater significance. Accordingly the functional dis- tribution of net state and local bond issues! for the years 1915 to 1929 is shown in Table 17. Reference to this table indi- cates that for the entire period roads, streets, and bridges accounted for the largest proportion of state and local issues. It is not to be inferred that the same was true for each year of the period, although this was the case in all except four years. The proportion of the total attributable to roads, streets, and bridges did not show an unusual change because of the issue of state bonds for highway purposes in 1922 and later years. Since 1921 the proportion of local bonds issued for this purpose has been relatively lower than in 1921 and preceding years, with the result that when state bonds are included the relationship between bonds for roads, streets, and bridges and total bonds did not change appreciably. The year 1928 forms an exception to the last statement. In that year no state highway bonds were issued, and conse- quently the amount of $2.2 million represents only local bonds issued for highway purposes. Other important functions for which bonds were issued during this period were sewers and drainage, schools and school buildings, and general buildings. The issues for these purposes in each case showed considerable variation. The issues for schools and school purposes comprised a consider- able proportion of the total in all but two years, while those 1 Total of new bonds issued less those for refunding.