business-related metrics as of or for the year ended december 31 .

Table: ( in billions except ratios ) 2003 2002 change loan and lease receivables $ 43.2 $ 37.4 16% ( 16 % ) average loan and lease receivables 41.7 31.7 32 automobile origination volume 27.8 25.3 10 automobile market share 6.1% ( 6.1 % ) 5.7% ( 5.7 % ) 40bp 30+ day delinquency rate 1.46 1.54 -8 ( 8 ) net charge-off ratio 0.41 0.51 -10 ( 10 ) overhead ratio 35 36 -100 ( 100 )

crb is the no . 1 bank in the new york tri-state area and a top five bank in texas ( both ranked by retail deposits ) , providing payment , liquidity , investment , insurance and credit products and services to three primary customer segments : small busi- ness , affluent and retail . within these segments , crb serves 326000 small businesses , 433000 affluent consumers and 2.6 million mass-market consumers . crb 2019s continued focus on expanding customer relationships resulted in a 14% ( 14 % ) increase in core deposits ( for this purpose , core deposits are total deposits less time deposits ) from december 31 , 2002 , and a 77% ( 77 % ) increase in the cross-sell of chase credit products over 2002 . in 2003 , mortgage and home equity originations through crb 2019s distribution channels were $ 3.4 billion and $ 4.7 billion , respectively . branch-originated credit cards totaled 77000 , contributing to 23% ( 23 % ) of crb customers holding chase credit cards . crb is compensated by cfs 2019s credit businesses for the home finance and credit card loans it origi- nates and does not retain these balances . chase regional banking while crb continues to position itself for growth , decreased deposit spreads related to the low-rate environment and increased credit costs resulted in an 80% ( 80 % ) decline in crb operating earnings from 2002 . this decrease was partly offset by an 8% ( 8 % ) increase in total average deposits . operating revenue of $ 2.6 billion decreased by 9% ( 9 % ) compared with 2002 . net interest income declined by 11% ( 11 % ) to $ 1.7 billion , primarily attributable to the lower interest rate environment . noninterest revenue decreased 6% ( 6 % ) to $ 927 million due to lower deposit service fees , decreased debit card fees and one-time gains in 2002 . crb 2019s revenue does not include funding profits earned on its deposit base ; these amounts are included in the results of global treasury . operating expense of $ 2.4 billion increased by 7% ( 7 % ) from 2002 . the increase was primarily due to investments in technology within the branch network ; also contributing were higher compensation expenses related to increased staff levels and higher severance costs as a result of continued restructuring . this increase in operating caf is the largest u.s . bank originator of automobile loans and leases , with more than 2.9 million accounts . in 2003 , caf had a record number of automobile loan and lease originations , growing by 10% ( 10 % ) over 2002 to $ 27.8 billion . loan and lease receivables of $ 43.2 billion at december 31 , 2003 , were 16% ( 16 % ) higher than at the prior year-end . despite a challenging operating environment reflecting slightly declining new car sales in 2003 and increased competition , caf 2019s market share among automobile finance companies improved to 6.1% ( 6.1 % ) in 2003 from 5.7% ( 5.7 % ) in 2002 . the increase in market share was the result of strong organic growth and an origination strategy that allies the business with manufac- turers and dealers . caf 2019s relationships with several major car manufacturers contributed to 2003 growth , as did caf 2019s dealer relationships , which increased from approximately 12700 dealers in 2002 to approximately 13700 dealers in 2003 . in 2003 , operating earnings were $ 205 million , 23% ( 23 % ) higher compared with 2002 . the increase in earnings was driven by continued revenue growth and improved operating efficiency . in 2003 , caf 2019s operating revenue grew by 23% ( 23 % ) to $ 842 million . net interest income grew by 33% ( 33 % ) compared with 2002 . the increase was driven by strong operating performance due to higher average loans and leases outstanding , reflecting continued strong origination volume and lower funding costs . operating expense of $ 292 million increased by 18% ( 18 % ) compared with 2002 . the increase in expenses was driven by higher average chase auto finance loans outstanding , higher origination volume and higher perform- ance-based incentives . caf 2019s overhead ratio improved from 36% ( 36 % ) in 2002 to 35% ( 35 % ) in 2003 , as a result of strong revenue growth , con- tinued productivity gains and disciplined expense management . credit costs increased 18% ( 18 % ) to $ 205 million , primarily reflecting a 32% ( 32 % ) increase in average loan and lease receivables . credit quality continued to be strong relative to 2002 , as evidenced by a lower net charge-off ratio and 30+ day delinquency rate . caf also comprises chase education finance , a top provider of government-guaranteed and private loans for higher education . loans are provided through a joint venture with sallie mae , a government-sponsored enterprise and the leader in funding and servicing education loans . chase education finance 2019s origination volume totaled $ 2.7 billion , an increase of 4% ( 4 % ) from last year . management 2019s discussion and analysis j.p . morgan chase & co . 42 j.p . morgan chase & co . / 2003 annual report .

Question: what was the 2003 improvement in the 30+ day delinquency rate , ( us$ b ) ?
Answer: 12%
Calculation: multiply(divide(8, const_100), 1.54)