On 4 April 2018, the source wrote (citation):

Palvelualojen liikevaihtokuvaajassa siirrytään käyttämään perusvuotta 2015=100 tammikuun 2018 tiedoista alkaen. Tiedot julkaistaan ensimmäisen kerran uudella perusvuodella 12.4.2018.

Perusvuoden vaihdon yhteydessä indeksit on laskettu uudelleen vuoden 2015 alusta. Tässä yhteydessä aineisto on saattanut tarkentua ja siinä on huomioitu mm. viimeisimmät luokitustietojen muutokset. [...]

That is:

Starting from data concerning January 2018, the base year 2015=100 will be introduced in the turnover of services. Data will be released for the first time with the new base year on 12 April 2018.

The indices are re-calculated from the beginning of 2015 in connection with the change of the base year. In this context, the data may have become revised and there the latest changes in the classification data are taken into consideration. [...]

In response, we have:

1. Archived the 45 predecessors (2010=100, January 1995 to December 2017) by renaming with an "_10" specifier, marking metadata as "discontinued", and segregating in the catalog. 
2. Created one-for-one replacements (2015=100). 
3. Expanded our extract with the remaining 57 series (at the one- and two-digit activity levels).
4. Assigned standard mnemonics to the replacements.

Dataset properties:

• Activity classification: TOL 2008 (a.k.a. SIC 2008, the national adaptation of NACE Rev. 2), scope of H to I, L to N, R, S
• Measurement: Fixed-based index relative to 2015 (Index 2015=100)
• Adjustment: Not seasonally adjusted (NSA), seasonally adjusted (SA), or trend (Trend)
• Native frequency: Monthly
• Start date: January 1995
• Subject to revision: Yes
• Lag: 75 days

The active series reside in the historical catalog (Finland » Industry » Turnover in service » 2015 = 100) and predecessors under the associated "discontinued" node. They include, for example:

• TNIPUB_10TM.IFIN = [DISCONTINUED] Turnover indices of other services: Publishing, (Index 2010=100, Trend)
• TNISVOAM.IFIN    = All other service activities [H to J; L to N; R to S], (Index 2015=100, SA)
• TNIAEUM.IFIN     = Arts; entertainment and recreation [R], (Index 2015=100, NSA)
• TNI58TM.IFIN     = Publishing activities [58], (Index 2015=100, Trend)

Additional branches include, for example:

• TNI60UM.IFIN  = Programming and broadcasting activities [60], (Index 2015=100, NSA)
• TNIPSTM.IFIN  = Professional; scientific and technical activities [M], (Index 2015=100, Trend)
• TNIPSDAM.IFIN = Legal and accounting activities; management consultancy activities [69 to 70], (Index 2015=100, SA)

Because catalog locations are subject to change, the upper-right search box on DataBuffet.com provides a "find in catalog" mode that accepts a mnemonic.

Please be aware that

In this dataset, the headline series is "other service activities", not "total". It is the non-consecutive aggregate of NACE Rev. 2 sections H to J; L; M to N; R to S (which span divisions 49 to 96, non-inclusive).

References

• Statistics » Turnover of service industries
• Description of statistics » Turnover of service industries
• Concepts and definitions » Turnover
• Classifications » Standard Industrial Classification TOL 2008

See also

• Data Change: Finland - Turnover index in construction - Rebased to 2015 (section F)
• Data Change: Finland - RSI - Rebased to 2015 (section G)
• Other recent operations on Finland