westrock company notes to consolidated financial statements fffd ( continued ) a reconciliation of the beginning and ending amount of gross unrecognized tax benefits is as follows ( in millions ) : .

2018
2017
2016
Balance at beginning of fiscal year
$148.9
$166.8
$106.6
Additions related to purchase accounting<sup>(1)</sup>
3.4
7.7
16.5
Additions for tax positions taken in current year
3.1
5.0
30.3
Additions for tax positions taken in prior fiscal years
18.0
15.2
20.6
Reductions for tax positions taken in prior fiscal years
(5.3)
(25.6)
(9.7)
Reductions due to settlement<sup>(2)</sup>
(29.4)
(14.1)
(1.3)
(Reductions) additions for currency translation adjustments
(9.6)
2.0
7.0
Reductions as a result of a lapse of the applicable statute oflimitations
(2.0)
(8.1)
(3.2)
Balance at end of fiscal year
$127.1
$148.9
$166.8

( 1 ) amounts in fiscal 2018 and 2017 relate to the mps acquisition .
adjustments in fiscal 2016 relate to the combination and the sp fiber acquisition .
( 2 ) amounts in fiscal 2018 relate to the settlement of state audit examinations and federal and state amended returns filed related to affirmative adjustments for which a there was a reserve .
amounts in fiscal 2017 relate to the settlement of federal and state audit examinations with taxing authorities .
as of september 30 , 2018 and 2017 , the total amount of unrecognized tax benefits was approximately $ 127.1 million and $ 148.9 million , respectively , exclusive of interest and penalties .
of these balances , as of september 30 , 2018 and 2017 , if we were to prevail on all unrecognized tax benefits recorded , approximately $ 108.7 million and $ 138.0 million , respectively , would benefit the effective tax rate .
we regularly evaluate , assess and adjust the related liabilities in light of changing facts and circumstances , which could cause the effective tax rate to fluctuate from period to period .
we recognize estimated interest and penalties related to unrecognized tax benefits in income tax expense in the consolidated statements of operations .
as of september 30 , 2018 , we had liabilities of $ 70.4 million related to estimated interest and penalties for unrecognized tax benefits .
as of september 30 , 2017 , we had liabilities of $ 81.7 million , net of indirect benefits , related to estimated interest and penalties for unrecognized tax benefits .
our results of operations for the fiscal year ended september 30 , 2018 , 2017 and 2016 include expense of $ 5.8 million , $ 7.4 million and $ 2.9 million , respectively , net of indirect benefits , related to estimated interest and penalties with respect to the liability for unrecognized tax benefits .
as of september 30 , 2018 , it is reasonably possible that our unrecognized tax benefits will decrease by up to $ 5.5 million in the next twelve months due to expiration of various statues of limitations and settlement of issues .
we file federal , state and local income tax returns in the u.s .
and various foreign jurisdictions .
with few exceptions , we are no longer subject to u.s .
federal and state and local income tax examinations by tax authorities for years prior to fiscal 2015 and fiscal 2008 , respectively .
we are no longer subject to non-u.s .
income tax examinations by tax authorities for years prior to fiscal 2011 , except for brazil for which we are not subject to tax examinations for years prior to 2005 .
while we believe our tax positions are appropriate , they are subject to audit or other modifications and there can be no assurance that any modifications will not materially and adversely affect our results of operations , financial condition or cash flows .
note 6 .
segment information we report our financial results of operations in the following three reportable segments : corrugated packaging , which consists of our containerboard mill and corrugated packaging operations , as well as our recycling operations ; consumer packaging , which consists of consumer mills , folding carton , beverage , merchandising displays and partition operations ; and land and development , which sells real estate primarily in the charleston , sc region .
following the combination and until the completion of the separation , our financial results of operations had a fourth reportable segment , specialty chemicals .
prior to the hh&b sale , our consumer packaging segment included hh&b .
certain income and expenses are not allocated to our segments and , thus , the information that .

Question: Analyse this data from a financial earnings document. by what percent did the balance of tax benefits increase between the beginning of 2016 and the end of 2018?
Choices:
5.2
127.1
-0.19231
1
0.19231
Correct choice index: 4