The provision for income taxes differs from the amount computed by applying the statutory federal tax rate to income before income taxes. The sources and tax effects of the differences in the total income tax provision are as follows (amounts in millions):
(1) The release of prior year tax positions during fiscal 2019 increased the basic and diluted net income per common share by $0.32 and $0.30, respectively. The release of prior year tax positions during fiscal 2018 increased the basic and diluted net income per common share by $0.05. The release of prior year tax positions during fiscal 2017 increased the basic and diluted net income per common share by $0.17 and $0.15, respectively.
The foreign tax rate differential benefit primarily relates to the Company's operations in Thailand, Malta and Ireland. The Company's Thailand manufacturing operations are currently subject to numerous tax holidays granted to the Company based on its investment in property, plant and equipment in Thailand. The Company's tax holiday periods in Thailand expire between fiscal 2022 and 2026, however, the Company actively seeks to obtain new tax holidays. The Company does not expect the future expiration of any of its tax holiday periods in Thailand to have a material impact on its effective tax rate. The Company’s Microsemi operations in Malaysia are subject to a tax holiday that effectively reduces the income tax rate in that jurisdiction. Microsemi’s tax holiday in Malaysia was granted in 2009 and is effective through December 2019, subject to continued compliance with the tax holiday’s requirements. The aggregate dollar expense derived from these tax holidays approximated $0.1 million in fiscal 2019. The aggregate dollar benefit derived from these tax holidays approximated $6.2 million and $13.2 million in fiscal 2018 and 2017, respectively. The impact of the tax holidays during fiscal 2019 did not impact basic and diluted net income per common share. The impact of the tax holidays during fiscal 2018 increased the basic and diluted net income per common share by $0.03 and $0.02, respectively. The impact of the tax holidays during fiscal 2017 increased the basic and diluted net income per common share by $0.06.
Table:
 |  | Year Ended March 31, | 
 | 2019 | 2018 | 2017
Computed expected income tax provision | $43.0 | $232.6 | $31.4
State income taxes, net of federal benefit | (8.7) | (1.3) | (4.6)
Foreign income taxed at lower than the federal rate | (94.0) | (208.8) | (105.0)
Impact of the Act - one-time transition tax, net of foreign tax credits | 13.1 | 653.7 | —
Impact of the Act - deferred tax effects, net of valuation allowance | — | (136.7) | —
Global intangible low-taxed income | 95.4 | — | —
Business realignment | (90.6) | — | —
Increases related to current year tax positions | 9.0 | 32.0 | 53.7
Decreases related to prior year tax positions (1) | (75.1) | (11.3) | (36.3)
Share-based compensation | (13.3) | (27.2) | (25.0)
Research and development tax credits | (27.5) | (17.0) | (12.8)
Intercompany prepaid tax asset amortization | 5.2 | 7.4 | 7.9
Foreign exchange | 4.6 | (20.5) | (1.7)
Other | (2.6) | (0.5) | 9.8
Change in valuation allowance | (9.9) | (20.5) | 1.8
Total income tax provision (benefit) | $(151.4) | $481.9 | $(80.8)


Question: How many years did Intercompany prepaid tax asset amortization exceed $7 million?
Answer: 2
Calculation: 2018##2017