entergy corporation and subsidiaries management's financial discussion and analysis methodology of computing massachusetts state income taxes resulting from legislation passed in the third quarter 2008 , which resulted in an income tax benefit of approximately $ 18.8 million .
these factors were partially offset by : income taxes recorded by entergy power generation , llc , prior to its liquidation , resulting from the redemption payments it received in connection with its investment in entergy nuclear power marketing , llc during the third quarter 2008 , which resulted in an income tax expense of approximately $ 16.1 million ; book and tax differences for utility plant items and state income taxes at the utility operating companies , including the flow-through treatment of the entergy arkansas write-offs discussed above .
the effective income tax rate for 2007 was 30.7% ( 30.7 % ) .
the reduction in the effective income tax rate versus the federal statutory rate of 35% ( 35 % ) in 2007 is primarily due to : a reduction in income tax expense due to a step-up in the tax basis on the indian point 2 non-qualified decommissioning trust fund resulting from restructuring of the trusts , which reduced deferred taxes on the trust fund and reduced current tax expense ; the resolution of tax audit issues involving the 2002-2003 audit cycle ; an adjustment to state income taxes for non-utility nuclear to reflect the effect of a change in the methodology of computing new york state income taxes as required by that state's taxing authority ; book and tax differences related to the allowance for equity funds used during construction ; and the amortization of investment tax credits .
these factors were partially offset by book and tax differences for utility plant items and state income taxes at the utility operating companies .
see note 3 to the financial statements for a reconciliation of the federal statutory rate of 35.0% ( 35.0 % ) to the effective income tax rates , and for additional discussion regarding income taxes .
liquidity and capital resources this section discusses entergy's capital structure , capital spending plans and other uses of capital , sources of capital , and the cash flow activity presented in the cash flow statement .
capital structure entergy's capitalization is balanced between equity and debt , as shown in the following table .
the decrease in the debt to capital percentage from 2008 to 2009 is primarily the result of an increase in shareholders' equity primarily due to an increase in retained earnings , partially offset by repurchases of common stock , along with a decrease in borrowings under entergy corporation's revolving credit facility .
the increase in the debt to capital percentage from 2007 to 2008 is primarily the result of additional borrowings under entergy corporation's revolving credit facility. .

2009
2008
2007
Net debt to net capital at the end of the year
53.5%
55.6%
54.7%
Effect of subtracting cash from debt
3.8%
4.1%
2.9%
Debt to capital at the end of the year
57.3%
59.7%
57.6%

.

Question: Analyse this data from a financial earnings document. what is the change in percentage points in debt-to-capital ratio from 2008 to 2009?
Choices:
22.3
-24.7
2.4
0
-2.4
Correct choice index: 4