notes to consolidated financial statements ( continued ) note 6 2014shareholders 2019 equity ( continued ) the following table summarizes activity in other comprehensive income related to derivatives , net of taxes , held by the company ( in millions ) : .

Table:
 | 2007 | 2006 | 2005
changes in fair value of derivatives | $ -1 ( 1 ) | $ 11 | $ 7
adjustment for net ( losses ) /gains realized and included in net income | -2 ( 2 ) | -12 ( 12 ) | 1
change in unrealized gains on derivative instruments | $ -3 ( 3 ) | $ -1 ( 1 ) | $ 8
the tax effect related to the changes in fair value of derivatives was $ 1 million , $ ( 8 ) million , and $ ( 3 ) million for 2007 , 2006 , and 2005 , respectively .
the tax effect related to derivative gains/losses reclassified from other comprehensive income to net income was $ 2 million , $ 8 million , and $ ( 2 ) million for 2007 , 2006 , and 2005 , respectively .
employee benefit plans 2003 employee stock plan the 2003 employee stock plan ( the 2018 20182003 plan 2019 2019 ) is a shareholder approved plan that provides for broad- based grants to employees , including executive officers .
based on the terms of individual option grants , options granted under the 2003 plan generally expire 7 to 10 years after the grant date and generally become exercisable over a period of four years , based on continued employment , with either annual or quarterly vesting .
the 2003 plan permits the granting of incentive stock options , nonstatutory stock options , rsus , stock appreciation rights , stock purchase rights and performance-based awards .
during 2007 , the company 2019s shareholders approved an amendment to the 2003 plan to increase the number of shares authorized for issuance by 28 million shares .
1997 employee stock option plan in august 1997 , the company 2019s board of directors approved the 1997 employee stock option plan ( the 2018 20181997 plan 2019 2019 ) , a non-shareholder approved plan for grants of stock options to employees who are not officers of the company .
based on the terms of individual option grants , options granted under the 1997 plan generally expire 7 to 10 years after the grant date and generally become exercisable over a period of four years , based on continued employment , with either annual or quarterly vesting .
in october 2003 , the company terminated the 1997 plan and no new options can be granted from this plan .
1997 director stock option plan in august 1997 , the company 2019s board of directors adopted a director stock option plan ( the 2018 2018director plan 2019 2019 ) for non-employee directors of the company , which was approved by shareholders in 1998 .
pursuant to the director plan , the company 2019s non-employee directors are granted an option to acquire 30000 shares of common stock upon their initial election to the board ( 2018 2018initial options 2019 2019 ) .
the initial options vest and become exercisable in three equal annual installments on each of the first through third anniversaries of the grant date .
on the fourth anniversary of a non-employee director 2019s initial election to the board and on each subsequent anniversary thereafter , the director will be entitled to receive an option to acquire 10000 shares of common stock ( 2018 2018annual options 2019 2019 ) .
annual options are fully vested and immediately exercisable on their date of grant .
rule 10b5-1 trading plans certain of the company 2019s executive officers , including mr .
timothy d .
cook , mr .
peter oppenheimer , mr .
philip w .
schiller , and dr .
bertrand serlet , have entered into trading plans pursuant to .

Question: what was the change in unrealized gains on derivative instruments between 2006 and 2007?
Answer: 2
Calculation: subtract(const_m1, -3)