If you specify a negative scale, Oracle Database rounds the actual data to the specified number of places to the left of the decimal point. For example, specifying (7,-2) means Oracle Database rounds to the nearest hundredths, as shown in Table 26-1.
McCann (2000) found that households in communities with good transit use save an average of about $3,000 annually on transportation costs. Litman (2004) found annual transportation cost savings of about $1,300 per household in cities with well-established rail transit systems compared with cities that lack rail.
If the social costs of transit are 2 cents per passenger mile, the total costs of transit are 86 cents and the subsidies are 66 cents per passenger mile. So transit costs are nearly three time auto costs, while transit subsidies are more than eight times auto costs.