Comparing shows across countries when the audit rules are not the same

A portfolio review puts a German show and a French show on the same slide. The German one shows 45,500 square metres of net space. The French one shows 42,000. Somebody concludes the German show is 8 per cent larger and starts allocating investment accordingly.

Comparing shows across countries breaks at exactly this point, because the two numbers were produced under different rules by different bodies, and in this case the two floors could be identical. The certificates are honest. They are answering different questions.

The same square metre counts in one country and not the other

UFI's Euro Fair Statistics for 2022, published in November 2023, is the document that makes this legible, because it prints the definitions of eleven national certifying bodies next to each other before it prints any data. The report covers the certified figures of 1,826 exhibitions from 14 countries, and UFI is direct about what that means in practice, writing that "methods may vary slightly from country to country but all the national bodies who have taken part in this study guarantee the quality of the statistics they have provided".

Slightly is doing some work in that sentence. Take net exhibition space.

FKM in Germany defines net exhibition space as the exhibitor stand area plus space for special shows, which are the stands and demonstrations dealing with the theme of the event independently of exhibitors. UNIMEV in France gives the area occupied by exhibitors and co-exhibitors, and states that it "does not include in this case the area used for features in relation with the theme of the exhibition".

So the German and French shows above may both have 42,000 square metres of exhibitor stand area, with the German show additionally running 3,500 square metres of special show. The German certificate reads 45,500. The French certificate reads 42,000. The gap is 3,500 square metres, which is 8.3 per cent of 42,000, and no exhibitor has rented one extra metre.

There is a second split on the same field. Finland's Association of Trade Fair and Event Organisers states that "areas given free of charge to exhibitors are not counted". BDO in Portugal counts contracted space "whether it is paid or unpaid". A show giving 2,000 square metres to a sponsor, a start-up zone and an association partner reports 2,000 square metres more in Lisbon than in Helsinki.

What does a certified visitor figure mean in each market?

The visitor side diverges further, because the bodies disagree about both the unit and the population.

FKM in Germany calculates visitor figures from the number of entries to the trade fair centre, with a maximum of one entry registered per visitor per day. UNIMEV in France publishes total visits, and states plainly that "a journalist is counted as visitor". FKM Austria excludes a whole class of people, noting that "complimentary tickets, exhibitor tickets, press tickets etc. have not been taken into consideration". ISFCERT in Italy admits free entrants conditionally, since "visitors admitted free of charge are counted only if they give elements for their qualification and identification". CENTREX, which certifies for Bulgaria, the Czech Republic, Hungary and Poland, has a rule for consumer shows that has no analogue anywhere else in the document: four visitors are counted for each family ticket sold.

Two of those bodies also publish visits where others publish visitors. BDO in Portugal states that the figures it supplies to the report "concern the number of total visits: total number of visitors plus the total number of repeat visits", and UNIMEV does the same for France. A German figure built from daily admissions and a French figure built from total visits are closer to each other than either is to a count of distinct people, which is a distinction the word visitor on both certificates does nothing to signal.

Put one show through three of those rules. A five-day trade fair draws 24,000 distinct people who make 38,400 admissions between them, an average of 1.6 days each. Of those admissions, 1,400 are press and 6,700 belong to holders of complimentary tickets, and 2,300 of the complimentary admissions came from people who gave no identifying details at registration.

Under the French treatment the published figure is total visits with journalists included: 38,400.

Under the Italian treatment, stripping only the unidentifiable free admissions: 36,100.

Under the Austrian treatment, dropping press and complimentary tickets: 38,400 minus 1,400 minus 6,700, which is 30,300.

The same five days, the same turnstiles, three certified figures spanning 8,100 admissions, or 21 per cent of the largest. Each one is correct under the rules it was produced under, and a slide putting two of them side by side is not measuring the shows.

Exhibitor counts break on collective stands

The third field on any certificate is the exhibitor count, and the divergence there is concentrated in one place: national pavilions and grouped participations.

AFE in Spain draws the line by area, stating that in a collective or grouped participation "the different exhibitors are considered direct when they occupy an area of at least 9 m2. Exhibitors occupying less than 9 m2 are considered indirect". UFI's own auditing rules, published in June 2021, draw it by autonomy instead: co-exhibitors count as direct exhibitors where they occupy their own area, appear under their own name and present their own products or services with their own staff.

A country pavilion of 40 companies each on a 6 square metre pod, each with its own signage and its own staff, therefore adds 40 direct exhibitors under UFI's rules and zero under the Spanish area test, with the pavilion organiser counting as the single direct exhibitor instead. A show with six such pavilions carries a swing of more than 200 exhibitors between the two conventions, on an identical floor plan.

This is the field where a competitor comparison most often goes wrong, because exhibitor count is the number exhibition sales teams quote at each other and the one least likely to carry a footnote. Whether the count on a given certificate includes co-exhibitors is a question you can answer in one email, and telling an organiser statement apart from a certified figure is the prior step before you bother asking.

Which body signed it, and to whose rules

FKM has been doing this longer than most. Its own account is that in 1965 six German trade fair companies decided to create uniform standards for determining figures for exhibitors, floor space and visitors, and that it has operated since 1966 (FKM, 2026). Sixty years of one definition applied consistently is worth a great deal, and it is worth precisely nothing as a guarantee that the definition matches anyone else's.

Some bodies sit inside a wider accreditation chain. ISFCERT in Italy records that it has been appointed by ACCREDIA, the Italian accreditation body, since 2013, to audit events against published international exhibition standards. Others certify across borders: CENTREX covers four countries from Budapest, and FKM's own definitions page in the Euro Fair report notes that it certifies in Germany and some events in Italy. So the country a show is held in does not reliably tell you whose rules its figures were produced under, which is the map worth having in front of you before you start a cross-border comparison.

How do you write a comparability note that survives a board meeting?

Four lines next to any cross-border figure, and they take about ten minutes each once you have the certificates.

• The body and the edition. Who signed it and for which dates.
• The unit. Visitors counted once, admissions capped at one per day, or total visits.
• The inclusions. Whether press, complimentary entrants, exhibitor staff and special show space are in or out.
• The residual you could not resolve, expressed as a range rather than an adjustment. If you cannot separate the press from the visitor count, say the comparable figure lies between two values and name them both.

That fourth line is the one people want to skip, and it is the one that keeps the note honest. An adjustment you cannot evidence is a new unaudited number wearing a certificate's clothes.

It is worth knowing how much of a market you can even reach this way. UFI (2023) estimates that the certified events in the 2022 Euro Fair report accounted for around 47 per cent of the European exhibition market by net space rented, which means roughly half the space in Europe changed hands at events with no certified figures at all. For those shows the comparability question never arises, because there is nothing to compare against, and the entry in your tracker should say so.

Where this stops

You cannot rebuild a foreign certificate onto your own definition without the components, and most published certificates give totals.

If a French certificate reports 78,400 visits and nothing else, you can convert it to unique visitors only by assuming a repeat-visit ratio, and the ratio you know is your own. Applying your 1.28 visits per visitor to their file yields 61,250 implied unique visitors, and applying a plausible range of 1.15 to 1.50 yields anywhere from 52,267 to 68,174. That is a spread of nearly 16,000 people, which is wide enough that the comparison should be reported as a range or abandoned.

The other limit is that harmonising the definitions does not harmonise the markets. A German trade fair and a French one with identical rebuilt figures still differ in how buyers travel, how long they stay and what a visit is worth to an exhibitor, and the international share of each audience is itself computed under rules worth reading separately. Comparability of the count is the floor of a cross-border comparison, and the rest of the measurement standards work sits on top of it.

Start with one pair. Pull the certificates for your nearest foreign competitor and your own most recent edition, put the two definitions in one column each, and mark every line where they disagree. The count of disagreements is your comparability gap, and it usually takes an afternoon to find.