EIO Eaton Vance Ohio Municipal Bond Fund Common Shared of Befeficial Interest, $.01 Par Value

Eaton Vance Insured Ohio Municipal Bond Fund (AMEX:EIO) (the �Fund�), a closed-end management investment company, today announced the earnings of the Fund for the three and six-month periods ended March 31, 2008. The Fund�s fiscal year ends on September 30, 2008. For the three months ended March 31, 2008, the Fund had net investment income of $598,367 ($0.238 per common share). From this amount, the Fund paid dividends on preferred shares of $199,532 (equal to $0.080 for each common share), resulting in net investment income after the preferred dividends of $398,835, or $0.158 per common share. The Fund�s net investment income for the six months ended March 31, 2008 was $1,198,414 ($0.477 per common share, before deduction of the preferred share dividends totaling $0.158 per common share), resulting in net investment income after the preferred dividends of $0.319 per common share. In comparison, for the three months ended March 31, 2007, the Fund had net investment income of $605,387 ($0.241 per common share). From this amount, the Fund paid dividends on preferred shares of $178,955 (equal to $0.071 for each common share), resulting in net investment income after the preferred dividends of $426,432, or $0.170 per common share. The Fund�s net investment income for the six months ended March 31, 2007 was $1,213,197 ($0.483 per common share, before deduction of the preferred share dividends totaling $0.145 per common share), resulting in net investment income after the preferred dividends of $0.338 per common share. Net realized and unrealized losses for the three months ended March 31, 2008 were $3,612,159 ($1.433 per common share). The Fund�s net realized and unrealized losses for the six months ended March 31, 2008 were $4,704,178 ($1.868 per common share). In comparison, net realized and unrealized losses for the three months ended March 31, 2007 were $194,570 ($0.070 per common share). The Fund�s net realized and unrealized gains for the six months ended March 31, 2007 were $327,973 ($0.138 per common share). On March 31, 2008, net assets of the Fund applicable to common shares were $32,938,902. The net asset value per common share on March 31, 2008 was $13.11 based on 2,513,365 common shares outstanding. In comparison, on March 31, 2007, net assets of the Fund applicable to common shares were $38,864,950. The net asset value per common share on March 31, 2007 was $15.47 based on 2,512,727 common shares outstanding. The Fund is managed by Eaton Vance Management, a subsidiary of Eaton Vance Corp., which is listed on the New York Stock Exchange under the symbol EV. Eaton Vance and its affiliates had $159.1 billion in assets under management on April 30, 2008. Eaton Vance Management will make available periodic summary information regarding portfolio investments. Those interested should call Eaton Vance Management at (800) 262-1122. EATON VANCE INSURED OHIO MUNICIPAL BOND FUND SUMMARY OF RESULTS OF OPERATIONS (in thousands, except per share amounts) � � � � � Three Months Ended Six Months Ended March 31, March 31, � 2008 � � 2007 � � 2008 � � 2007 � Net investment income $ 598 $ 605 $ 1,198 $ 1,213 Net realized and unrealized gains (losses) on investments (3,612 ) (195 ) (4,704 ) 328 Preferred dividends paid from net investment income � (200 ) � (179 ) � (396 ) � (364 ) Net increase (decrease) in net assets from operations $ (3,214 ) $ 231 � $ (3,902 ) $ 1,177 � � Earnings per Common Share Outstanding Net investment income $ 0.238 $ 0.241 $ 0.477 $ 0.483 Net realized and unrealized gains (losses) on investments (1.433 ) (0.070 ) (1.868 ) 0.138 Preferred dividends paid from net investment income � (0.080 ) � (0.071 ) � (0.158 ) � (0.145 ) Net increase (decrease) in net assets from operations $ (1.275 ) $ 0.100 � $ (1.549 ) $ 0.476 � � Net investment income $ 0.238 $ 0.241 $ 0.477 $ 0.483 Preferred dividends paid from net investment income � (0.080 ) � (0.071 ) � (0.158 ) � (0.145 ) Net investment income after preferred dividends $ 0.158 � $ 0.170 � $ 0.319 � $ 0.338 � � Net Asset Value at March 31 (Common Shares) Net assets (000) $ 32,939 $ 38,865 Shares outstanding (000) 2,513 2,513 Net asset value per share outstanding $ 13.11 $ 15.47 � Market Value Summary (Common Shares) Market price on AMEX at March 31 $ 12.04 $ 15.20 High market price (period ended March 31) $ 14.40 $ 15.50 Low market price (period ended March 31) $ 11.85 $ 14.32