"When using the Chart Library, regularly charts are rendered unusable due to invalid spikes in the data. E.g. look at the RIEHE index (1 year daily or 5 year weekly view). The spike at 900,000 is clearly visible and renders the graph totally unreadable with a price at approximately 10K. Would it be so difficult to chunk off any spike in the data of let's say 50% versus preceding and following price, or at least to provide the chart user with the capability to do so? Thanks in advance"

And

"Please see my previous message regarding spikes in the Chart Library with respect to RIEHCLTR (Oct 2010 spike), NLR (May 2010 spike), RICIM (Feb 2007 spike), RIEHM (Sep 2008, Aug 2009, March 2011 spikes) and no doubt many more."

Eoin Treacy's view Thank you for these emails addressing an issue which may be of interest to other subscribers. The Fullermoney Chart Library is populated with a Bloomberg data feed. In turn they rely on fund and index providers such as Rogers for price history. When spikes occur this is generally because of an inconsistency in a component of the price series. I have messaged the Bloomberg help desk to ask them to contact the price provider in order to correct the spikes you mention. In the meantime you may wish to view the above instruments as line charts which will iron out the errata.

With regard to NLR, the downward spike on May 6th 2010 was as a result of the 'flash crash'. This event had a one day effect on a large number of ETFs. It will not be excised from the price history because it did occur and had a considerable effect on investor sentiment at the time.