american tower corporation and subsidiaries notes to consolidated financial statements when they are determined uncollectible . such determination includes analysis and consideration of the particular conditions of the account . changes in the allowances were as follows for the years ended december 31 , ( in thousands ) : .

Table:
 | 2012 | 2011 | 2010
balance as of january 1 | $ 24412 | $ 22505 | $ 28520
current year increases | 8028 | 17008 | 16219
write-offs net of recoveries and other | -12034 ( 12034 ) | -15101 ( 15101 ) | -22234 ( 22234 )
balance as of december 31 | $ 20406 | $ 24412 | $ 22505
functional currency 2014as a result of changes to the organizational structure of the company 2019s subsidiaries in latin america in 2010 , the company determined that effective january 1 , 2010 , the functional currency of its foreign subsidiary in brazil is the brazilian real .
from that point forward , all assets and liabilities held by the subsidiary in brazil are translated into u.s .
dollars at the exchange rate in effect at the end of the applicable reporting period .
revenues and expenses are translated at the average monthly exchange rates and the cumulative translation effect is included in equity .
the change in functional currency from u.s .
dollars to brazilian real gave rise to an increase in the net value of certain non-monetary assets and liabilities .
the aggregate impact on such assets and liabilities was $ 39.8 million with an offsetting increase in accumulated other comprehensive income during the year ended december 31 , 2010 .
as a result of the renegotiation of the company 2019s agreements with grupo iusacell , s.a .
de c.v .
( 201ciusacell 201d ) , which included , among other changes , converting iusacell 2019s contractual obligations to the company from u.s .
dollars to mexican pesos , the company determined that effective april 1 , 2010 , the functional currency of certain of its foreign subsidiaries in mexico is the mexican peso .
from that point forward , all assets and liabilities held by those subsidiaries in mexico are translated into u.s .
dollars at the exchange rate in effect at the end of the applicable reporting period .
revenues and expenses are translated at the average monthly exchange rates and the cumulative translation effect is included in equity .
the change in functional currency from u.s .
dollars to mexican pesos gave rise to a decrease in the net value of certain non-monetary assets and liabilities .
the aggregate impact on such assets and liabilities was $ 33.6 million with an offsetting decrease in accumulated other comprehensive income .
the functional currency of the company 2019s other foreign operating subsidiaries is also the respective local currency .
all assets and liabilities held by the subsidiaries are translated into u.s .
dollars at the exchange rate in effect at the end of the applicable fiscal reporting period .
revenues and expenses are translated at the average monthly exchange rates .
the cumulative translation effect is included in equity as a component of accumulated other comprehensive income .
foreign currency transaction gains and losses are recognized in the consolidated statements of operations and are the result of transactions of a subsidiary being denominated in a currency other than its functional currency .
cash and cash equivalents 2014cash and cash equivalents include cash on hand , demand deposits and short-term investments , including money market funds , with remaining maturities of three months or less when acquired , whose cost approximates fair value .
restricted cash 2014the company classifies as restricted cash all cash pledged as collateral to secure obligations and all cash whose use is otherwise limited by contractual provisions , including cash on deposit in reserve accounts relating to the commercial mortgage pass-through certificates , series 2007-1 issued in the company 2019s securitization transaction and the secured cellular site revenue notes , series 2010-1 class c , series 2010-2 class c and series 2010-2 class f , assumed by the company as a result of the acquisition of certain legal entities from unison holdings , llc and unison site management ii , l.l.c .
( collectively , 201cunison 201d ) . .

Question: what was the average bad debt allowance for the past three years , in billions?
Answer: 22441
Calculation: table_average(balance as of december 31, none)