Right now I'm trawling through the FTSE 100 (UKX) and double-checking for blue chips that may be flattering their profits.

You see, many companies these days report "underlying" earnings, which are calculated by excluding costs the firm deems to be "exceptional." Trouble is, some companies are more cavalier than others when it comes to sweeping awkward expenses away from the headline figures.

Today I'm looking at Aviva (LSE: AV.L) (NYSE: AV) to see if its reported earnings have been distorted significantly by exceptional, one-off, or unusual items. I've extracted the following statistics courtesy of S&P Capital IQ:

Year to 31 December






Profit before unusual items* 2,616 1,372 3,674 1,228 390
Restructuring charges* (153) (505) (388) (225) (268)
Goodwill impairment (10) (48) (30) (3) (160)
Gains on sales of assets 154 21 459 204 575
Asset writedowns* (760) (3,150) (1,029) 449 98
Other unusual items* - (58) (674) 286 -

*in millions of pounds.

While annual figures can provide some insight into how a business has performed, I reckon looking back over several years provides a better view of possible problems in relation to one-off costs.

So between 2007 and 2011, my stats tell me Aviva reported cumulative profits before exceptional items and tax of 9.3 billion pounds. However, aggregate exceptional costs came to 5.2 billion pounds -- equivalent to a huge 56% of cumulative "underlying" profits.

There is only one thing more complex than the accounts of a bank. And that's the accounts of an insurance company. Aviva is no exception.

Here, we have another company that's guilty of serial restructuring costs as it continually tries to reshape its vast array of domestic and international businesses. Over the last five years, it has incurred costs of around 1.5 billion pounds that have been classed as restructuring by our data source. With the recent departure of its CEO, it wouldn't be surprising to see further restructuring costs in the next few years.

Aviva has also had to make charges through its profit and loss account for any estimated changes in the long-term value of its assets, and these can be seen in the large amounts deducted in both 2008 and 2009.

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