( c ) includes the effects of items not considered in the assessment of the operating performance of our business segments which increased operating profit by $ 230 million , $ 150 million after tax ( $ 0.34 per share ) .also includes expenses of $ 16 million , $ 11 million after tax ( $ 0.03 per share ) for a debt exchange , and a reduction in income tax expense of $ 62 million ( $ 0.14 per share ) resulting from a tax benefit related to claims we filed for additional extraterritorial income exclusion ( eti ) tax benefits .on a combined basis , these items increased earnings by $ 201 million after tax ( $ 0.45 per share ) .( d ) includes the effects of items not considered in the assessment of the operating performance of our business segments which , on a combined basis , increased operating profit by $ 173 million , $ 113 million after tax ( $ 0.25 per share ) .( e ) includes the effects of items not considered in the assessment of the operating performance of our business segments which decreased operating profit by $ 61 million , $ 54 million after tax ( $ 0.12 per share ) .also includes a charge of $ 154 million , $ 100 million after tax ( $ 0.22 per share ) for the early repayment of debt , and a reduction in income tax expense resulting from the closure of an internal revenue service examination of $ 144 million ( $ 0.32 per share ) .on a combined basis , these items reduced earnings by $ 10 million after tax ( $ 0.02 per share ) .( f ) includes the effects of items not considered in the assessment of the operating performance of our business segments which , on a combined basis , decreased operating profit by $ 7 million , $ 6 million after tax ( $ 0.01 per share ) .also includes a charge of $ 146 million , $ 96 million after tax ( $ 0.21 per share ) for the early repayment of debt .( g ) we define return on invested capital ( roic ) as net earnings plus after-tax interest expense divided by average invested capital ( stockholders 2019 equity plus debt ) , after adjusting stockholders 2019 equity by adding back adjustments related to postretirement benefit plans .we believe that reporting roic provides investors with greater visibility into how effectively we use the capital invested in our operations .we use roic to evaluate multi-year investment decisions and as a long-term performance measure , and also use it as a factor in evaluating management performance under certain of our incentive compensation plans .roic is not a measure of financial performance under generally accepted accounting principles , and may not be defined and calculated by other companies in the same manner .roic should not be considered in isolation or as an alternative to net earnings as an indicator of performance .we calculate roic as follows : ( in millions ) 2007 2006 2005 2004 2003 .
[['( in millions )', '2007', '2006', '2005', '2004', '2003'], ['net earnings', '$ 3033', '$ 2529', '$ 1825', '$ 1266', '$ 1053'], ['interest expense ( multiplied by 65% ( 65 % ) ) 1', '229', '235', '241', '276', '317'], ['return', '$ 3262', '$ 2764', '$ 2066', '$ 1542', '$ 1370'], ['average debt2 5', '$ 4416', '$ 4727', '$ 5077', '$ 5932', '$ 6612'], ['average equity3 5', '7661', '7686', '7590', '7015', '6170'], ['average benefit plan adjustments3 4 5', '3171', '2006', '1545', '1296', '1504'], ['average invested capital', '$ 15248', '$ 14419', '$ 14212', '$ 14243', '$ 14286'], ['return on invested capital', '21.4% ( 21.4 % )', '19.2% ( 19.2 % )', '14.5% ( 14.5 % )', '10.8% ( 10.8 % )', '9.6% ( 9.6 % )']]
1 represents after-tax interest expense utilizing the federal statutory rate of 35% ( 35 % ) .2 debt consists of long-term debt , including current maturities of long-term debt , and short-term borrowings ( if any ) .3 equity includes non-cash adjustments , primarily for unrecognized benefit plan actuarial losses and prior service costs in 2007 and 2006 , the adjustment for the adoption of fas 158 in 2006 , and the additional minimum pension liability in years prior to 2007 .4 average benefit plan adjustments reflect the cumulative value of entries identified in our statement of stockholders equity under the captions 201cpostretirement benefit plans , 201d 201cadjustment for adoption of fas 158 201d and 201cminimum pension liability . 201d the total of annual benefit plan adjustments to equity were : 2007 = $ 1706 million ; 2006 = ( $ 1883 ) million ; 2005 = ( $ 105 ) million ; 2004 = ( $ 285 ) million ; 2003 = $ 331 million ; 2002 = ( $ 1537 million ) ; and 2001 = ( $ 33 million ) .as these entries are recorded in the fourth quarter , the value added back to our average equity in a given year is the cumulative impact of all prior year entries plus 20% ( 20 % ) of the current year entry value .5 yearly averages are calculated using balances at the start of the year and at the end of each quarter. .

Question: what was the difference in return on invested capital from 2006 to 2007?
Answer: 2.2%