The components of our deferred tax assets and liabilities were as follows:
We provide for taxes on the undistributed earnings of foreign subsidiaries. We do not provide for taxes on other outside basis temporary differences of foreign subsidiaries as they are considered indefinitely reinvested outside the U.S. At May 31, 2019, the amount of temporary differences related to other outside basis temporary differences of investments in foreign subsidiaries upon which U.S. income taxes have not been provided was approximately $7.9 billion. If the other outside basis differences were recognized in a taxable transaction, they would generate foreign tax credits that would reduce the federal tax liability associated with the foreign dividend or the otherwise taxable transaction. At May 31, 2019, assuming a full utilization of the foreign tax credits, the potential net deferred tax liability associated with these other outside basis temporary differences would be approximately $1.5 billion.
Our net deferred tax assets were $2.4 billion and $1.3 billion as of May 31, 2019 and 2018, respectively. We believe that it is more likely than not that the net deferred tax assets will be realized in the foreseeable future. realization of our net deferred tax assets is dependent upon our generation of sufficient taxable income in future years in appropriate tax jurisdictions to obtain benefit from the reversal of temporary differences, net operating loss carryforwards and tax credit carryforwards. The amount of net deferred tax assets considered realizable is subject to adjustment in future periods if estimates of future taxable income change.
The valuation allowance was $1.3 billion at each of May 31, 2019 and 2018. Substantially all of the valuation allowances as of May 31, 2019 and 2018 related to tax assets established in purchase accounting and other tax credits. Any subsequent reduction of that portion of the valuation allowance and the recognition of the associated tax benefits associated with our acquisitions will be recorded to our provision for income taxes subsequent to our final determination of the valuation allowance or the conclusion of the measurement period (as defined above), whichever comes first.
Table:
 |  | May 31,
(in millions) | 2019 | 2018
Deferred tax assets: |  | 
Accruals and allowances | $541 | $567
Employee compensation and benefits | 646 | 664
Differences in timing of revenue recognition | 322 | 338
Basis of property, plant and equipment and intangible assets | 1,238 | —
Tax credit and net operating loss carryforwards | 3,717 | 2,614
Total deferred tax assets | 6,464 | 4,183
Valuation allowance | (1,266) | (1,308)
Total deferred tax assets, net | 5,198 | 2,875
Deferred tax liabilities: |  | 
Unrealized gain on stock | (78) | (78)
Acquired intangible assets | (973) | (1,254)
GILTI deferred | (1,515) | —
Basis of property, plant and equipment and intangible assets | — | (158)
Other | (200) | (48)
Total deferred tax liabilities | (2,766) | (1,538)
Net deferred tax assets | $2,432 | $1,337
recorded as: |  | 
Non-current deferred tax assets | $2,696 | $1,395
Non-current deferred tax liabilities (in other non-current liabilities) | (264) | (58)
Net deferred tax assets | $2,432 | $1,337


Question: What were the valuation allowances for 2019 related to?
Answer: Substantially all of the valuation allowances as of May 31, 2019 and 2018 related to tax assets established in purchase accounting and other tax credits.