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.
The total congestion cost, which is the value of wasted time and fuel, is estimated to have cost US urban areas $101 billion in 2010, or $713 per commuter. The largest urban areas, not surprisingly, incur the highest congestion costs (see figure 1).