These Instructions and Advice were prepared for internal use within the Valuation Office Agency as part of work towards a council tax revaluation in England that was due to take effect on 1 April 2007.  The government announced its intention to postpone the revaluation on 20th September 2005 and preparatory work for a revaluation in 2007 has now been stopped.

In October’s Management Board minutes we promised to bring you some more details on using a Computer Assisted Mass Appraisal system (CAMA) for Council Tax Reval 2007 in England. Here, we look at the reasoning behind CAMA and what the possible implementation of the system means for us.

So, why CAMA?
Governments across the world use CAMA systems to value properties electronically. The system uses specified categories of property data to produce a valuation. CAMA is not restricted to revaluations; it can also double as a powerful database, storing property information on large numbers of properties. Implementing CAMA would give us a unique opportunity to position ourselves as the central point in Government as the keeper and supplier of property data. Maintained and updated it would also support our day- to-day council tax work beyond Reval 2007.

CAMA would be a major step forward in the modernisation of the local taxation process producing accurate and consistent valuations across a wide range and number of properties electronically.

CAMA should allow us to identify specific valuations for the majority of properties, much more quickly than a manual valuation, freeing up more time for staff to concentrate on complex valuation cases and those, which fall outside the scope of CAMA. Given the degree of uncertainty around the council tax bands in 2007, EVERY property will probably need a specific numeric valuation so, when the bandings are finally agreed, properties can be allocated their banding quickly.

What happens now?
The recent business review carried out with the help of KPMG concluded that using CAMA for Reval 2007 looks feasible but before any final decisions can be made a number of areas must be explored. If the Agency goes ahead with a computer assisted reval it will be the largest single development of a CAMA anywhere in the world.

Such a significant undertaking means we need to carefully plan our approach so that the system is rigorously tested and crafted for the English housing market.
Broadly, our approach will be in three phases:

• Auditing our data
• Testing the feasibility of CAMA
• Piloting CAMA

DATA AUDIT
A data audit is crucial as a CAMA is only as good as the data it uses. The VOA holds the most extensive property data in the UK unfortunately much of it in hardcopy. We need to test our data to see if it’s reliable enough to successfully operate CAMA and therefore worthwhile data capturing onto a computer database.

Later this year we aim to randomly select 10000 properties across England to see what sort of data we hold and, from that establish the quantity and quality of data contained within our records for all 21 million properties in England. We will fully explore all the options for data sources and may approach outside organisations with a view to filling any information gaps.

At the same time the West Midlands Group will test our data against 9000 sales to establish what property attribute data we actually need to produce an accurate valuation. Property codes will be used to capture this information on a computerised system and tested to ensure they cover all the critical information and we don’t collect information that isn’t needed.

Alongside the audits we must work out how we can best capture all our property data electronically, in a format that a CAMA can successfully use. We are currently looking at ways to do this.

TESTING THE FEASIBILITY OF A CAMA
Once we have identified all the data for CAMA to work we can develop our requirements for the system in more detail and look at potential providers who can be involved in its design. We need to establish how CAMA could be developed for the VOA and configured for the English housing market. Input from Groups will be very important.
After this phase a decision can be taken whether to go ahead and pilot CAMA.

PILOT
During the pilot stage we will work with a number of suppliers to establish the suitability and accuracy of their models, given the data that the VOA can provide. Local expertise will be needed to confirm valuation significant areas where property values tend to act in the same way, so a CAMA can take these into account when producing a valuation. Training needs for everyone involved in the CT Reval will also be explored. An appropriate procurement strategy will be developed before the final selection of a supplier.

The decision to procure CAMA must be made by mid 2004. This will allow sufficient time for a mass manual valuation to take place should CAMA not prove viable for Reval 2007.