Investing Activities Net cash used in investing activities was $752.3 million, $404.2 million and $1,759.1 million in the years ended December 31, 2017, 2016 and 2015, respectively.
The increase in the year ended December 31, 2017 compared with the year ended December 31, 2016 was primarily due to the acquisition of Sevcon and higher capital expenditures, including tooling outlays, offset by the 2016 sales of Divgi-Warner and the Remy light vehicle aftermarket business.
The decrease in the year ended December 31, 2016 compared with the year ended December 31, 2015 was primarily driven by lower capital expenditures, including tooling outlays, the 2016 sales of Divgi-Warner and the Remy light vehicle aftermarket business and the 2015 acquisition of Remy and BERU Diesel.
Year over year capital spending increase of $59.4 million during the year ended December 31, 2017 is due to higher spending required for new program awards within the Drivetrain segment.
Year over year capital spending decrease of $76.7 million during the year ended December 31, 2016 was primarily due to lower spending on new buildings and building expansions.
Financing Activities Net cash used in financing activities was $362.5 million and $733.8 million in the years ended December 31, 2017 and 2016, respectively, and net cash provided by financing activities was $736.6 million in the year ended December 31, 2015.
The decrease in the year ended December 31, 2017 compared with the year ended December 31, 2016 was primarily due to lower debt repayments and treasury stock purchases.
The decrease in the year ended December 31, 2016 compared with the year ended December 31, 2015 was primarily driven by lower debt borrowings and higher debt repayments, partially offset by lower treasury stock purchases.
The Company's significant contractual obligation payments at December 31, 2017 are as follows:
## Table 0 ##
(a) Other postretirement employee benefits, excluding pensions, include anticipated future payments to cover retiree medical and life insurance benefits.
Refer to Note 11, "Retirement Benefit Plans," to the Consolidated Financial Statements in Item 8 of this report for disclosures related to the Company’s other postretirement employee benefits.
(b) Since the timing and amount of payments for funded defined benefit pension plans are usually not certain for future years such potential payments are not shown in this table.
Amount contained in “After 2022” column is for unfunded plans and includes estimated payments through 2027.
Refer to Note 11, "Retirement Benefit Plans," to the Consolidated Financial Statements in Item 8 of this report for disclosures related to the Company’s pension benefits.
(c) Refer to Note 4, "Income Taxes," to the Consolidated Financial Statements in Item 8 of this report for disclosures related to the Company’s income taxes.
We believe that the combination of cash from operations, cash balances, available credit facilities, and the universal shelf registration capacity will be sufficient to satisfy our cash needs for our current level of operations and our planned operations for the foreseeable future.
We will continue to balance our needs for internal growth, external growth, debt reduction and cash conservation.
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued) 77 The Company believes the assumptions and estimates used to determine the estimated fair value are reasonable.
Different assumptions could materially affect the estimated fair value.
The primary assumptions affecting the Company's December 31, 2017 goodwill quantitative, "step one," impairment review are as follows: ?
Discount rate: The Company used a 10.4% weighted average cost of capital (“WACC”) as the discount rate for future cash flows.
The WACC is intended to represent a rate of return that would be expected by a market participant.  ?
Operating income margin: The Company used historical and expected operating income margins, which may vary based on the projections of the reporting unit being evaluated.  ?
Revenue growth rate: The Company used a global automotive market industry growth rate forecast adjusted to estimate its own market participation for product lines.
In addition to the above primary assumptions, the Company notes the following risks to volume and operating income assumptions that could have an impact on the discounted cash flow models: ?
The automotive industry is cyclical and the Company's results of operations would be adversely affected by industry downturns.  ?
The Company is dependent on market segments that use our key products and would be affected by decreasing demand in those segments.  ?
The Company is subject to risks related to international operations.
Based on the assumptions outlined above, the impairment testing conducted in the fourth quarter of 2017 indicated the Company's goodwill assigned to the reporting unit with restructuring activity that was quantitatively assessed was not impaired and contained a fair value that exceeded the reporting unit's carrying value by more than 20%.
Additionally, for the reporting unit quantitatively assessed, sensitivity analyses were completed indicating that a one percent increase in the discount rate, a one percent decrease in the operating margin, or a one percent decrease in the revenue growth rate assumptions would not result in the carrying value exceeding the fair value.
The changes in the carrying amount of goodwill for the years ended December 31, 2017 and 2016 are as follows:
## Table 1 ##
* Acquisitions during 2017 relate to the Company's 2017 purchase of Sevcon.
Acquisitions during 2016 were related to the Company's fair value adjustments for the 2015 Remy acquisition, based on new information obtained during the measurement period.
** Divestitures relate to the Company's 2016 disposition of Remy light vehicle aftermarket business and Divgi-Warner Private Limited.
While we have remediated the previously-identified material weakness in our internal control over financial reporting, we may identify other material weaknesses in the future.
In November 2017, we restated our consolidated financial statements for the quarters ended April 1, 2017 and July 1, 2017 in order to correctly classify cash receipts from the payments on sold receivables (which are cash receipts on the underlying trade receivables that have already been securitized) to cash provided by investing activities (from cash provided by operating activities) within our condensed consolidated statements of cash flows.
In connection with these restatements, management identified a material weakness in our internal control over financial reporting related to the misapplication of Accounting Standards Update 2016-15.
Specifically, we did not maintain effective controls over the adoption of new accounting standards, including communication with the appropriate individuals in coming to our conclusions on the application of new accounting standards.
As a result of this material weakness, our management concluded that we did not maintain effective internal control over financial reporting as of April 1, 2017 and July 1, 2017.
While we have remediated the material weakness and our management has determined that our disclosure controls and procedures were effective as of December 30, 2017, there can be no assurance that our controls will remain adequate.
The effectiveness of our internal control over financial reporting is subject to various inherent limitations, including judgments used in decision-making, the nature and complexity of the transactions we undertake, assumptions about the likelihood of future events, the soundness of our systems, cost limitations, and other limitations.
If other material weaknesses or significant deficiencies in our internal control are discovered or occur in the future or we otherwise must restate our financial statements, it could materially and adversely affect our business and results of operations or financial condition, restrict our ability to access the capital markets, require us to expend significant resources to correct the weaknesses or deficiencies, subject us to fines, penalties, investigations or judgments, harm our reputation, or otherwise cause a decline in investor confidence.
Item 1B.
Unresolved Staff Comments.
None.
Item 2.
Properties.
Our corporate co-headquarters are located in Pittsburgh, Pennsylvania and Chicago, Illinois.
Our co-headquarters are leased and house certain executive offices, our U. S.  business units, and our administrative, finance, legal, and human resource functions.
We maintain additional owned and leased offices throughout the regions in which we operate.
We manufacture our products in our network of manufacturing and processing facilities located throughout the world.
As of December 30, 2017, we operated 83 manufacturing and processing facilities.
We own 80 and lease three of these facilities.
Our manufacturing and processing facilities count by segment as of December 30, 2017 was:
## Table 2 ##
We maintain all of our manufacturing and processing facilities in good condition and believe they are suitable and are adequate for our present needs.
We also enter into co-manufacturing arrangements with third parties if we determine it is advantageous to outsource the production of any of our products.
Item 3.
Legal Proceedings.
We are routinely involved in legal proceedings, claims, and governmental inquiries, inspections or investigations (“Legal Matters”) arising in the ordinary course of our business.
While we cannot predict with certainty the results of Legal Matters in which we are currently involved or may in the future be involved, we do not expect that the ultimate costs to resolve any of the Legal Matters that are currently pending will have a material adverse effect on our financial condition or results of operations.
Item 4.
Mine Safety Disclosures.
Not applicable.

Tables referenced above, in order (Table 0 first):
<table><tr><td>(millions of dollars)</td><td>Total</td><td>2018</td><td>2019-2020</td><td>2021-2022</td><td>After 2022</td></tr><tr><td>Other postretirement employee benefits, excluding pensions(a)</td><td>$138.3</td><td>$13.3</td><td>$23.9</td><td>$20.2</td><td>$80.9</td></tr><tr><td>Defined benefit pension plans(b)</td><td>50.2</td><td>3.5</td><td>9.1</td><td>9.8</td><td>27.8</td></tr><tr><td>Notes payable and long-term debt</td><td>2,200.1</td><td>84.6</td><td>391.4</td><td>603.1</td><td>1,121.0</td></tr><tr><td>Projected interest payments</td><td>904.2</td><td>82.9</td><td>145.2</td><td>114.2</td><td>561.9</td></tr><tr><td>Non-cancelable operating leases</td><td>78.3</td><td>23.0</td><td>28.1</td><td>15.4</td><td>11.8</td></tr><tr><td>Capital spending obligations</td><td>106.5</td><td>106.5</td><td>—</td><td>—</td><td>—</td></tr><tr><td>Income tax payments(c)</td><td>333.5</td><td>333.5</td><td>—</td><td>—</td><td>—</td></tr><tr><td>Total</td><td>$3,811.1</td><td>$647.3</td><td>$597.7</td><td>$762.7</td><td>$1,803.4</td></tr></table>
<table><tr><td></td><td colspan="2">2017</td><td colspan="2">2016</td></tr><tr><td>(millions of dollars)</td><td>Engine</td><td>Drivetrain</td><td>Engine</td><td>Drivetrain</td></tr><tr><td>Gross goodwill balance, January 1</td><td>$1,324.0</td><td>$880.2</td><td>$1,338.2</td><td>$921.5</td></tr><tr><td>Accumulated impairment losses, January 1</td><td>-501.8</td><td>-0.2</td><td>-501.8</td><td>-0.2</td></tr><tr><td>Net goodwill balance, January 1</td><td>$822.2</td><td>$880.0</td><td>$836.4</td><td>$921.3</td></tr><tr><td>Goodwill during the year:</td><td></td><td></td><td></td><td></td></tr><tr><td>Acquisitions*</td><td>—</td><td>125.8</td><td>—</td><td>-12.1</td></tr><tr><td>Held for sale</td><td>-7.3</td><td>—</td><td>—</td><td>—</td></tr><tr><td>Divestitures**</td><td>—</td><td>—</td><td>—</td><td>-24.2</td></tr><tr><td>Translation adjustment and other</td><td>42.9</td><td>18.2</td><td>-14.2</td><td>-5.0</td></tr><tr><td>Ending balance, December 31</td><td>$857.8</td><td>$1,024.0</td><td>$822.2</td><td>$880.0</td></tr></table>
<table><tr><td></td><td>Owned</td><td>Leased</td></tr><tr><td>United States</td><td>41</td><td>1</td></tr><tr><td>Canada</td><td>2</td><td>—</td></tr><tr><td>Europe</td><td>11</td><td>—</td></tr><tr><td>Rest of World</td><td>26</td><td>2</td></tr></table>

Question: When is Net goodwill balance, January 1 the largest?
Answer: 2016