Bank of Greece issued the following announcement.

1.Office Indices
Office price index
According to provisional data, in 2018 nominal prime office prices increased on average by 7.0% relative to 2017 for the country as a whole, against an increase of 1.8% in 2017. Broken down by region, in 2018 nominal prime office prices increased by 9.0% in Athens, 5.4% in Thessaloniki and 5.1% in the rest of Greece.
In the second half of 2018, nominal prime office prices for the country as a whole increased by 2.9% compared with the first half of 2018 (provisional data). The corresponding rates of increase were 4.1% in the second half of 2017 and 3.4% in the first half of 2018 compared with the previous half-year (revised data). According to regional data, in the second half of 2018 nominal prime office prices increased by 4.6% in the greater Athens area, 3.7% in Thessaloniki and 0.7% in the rest of Greece, compared with the first half of 2018.
Office rent index
In 2018, office rents for the entire country increased οn average by 1.9% in nominal terms (provisional data). The corresponding average annual rates of increase were 1.8% in Athens and 2.6% in the rest of Greece, whereas in Thessaloniki a marginal decrease of 0.3% was recorded.
In the second half of 2018, office rents for the country as a whole increased by 0.6% compared with the first half of 2018 (provisional data). The respective rates of increase were 1.6% in the second half of 2017 and 0.8% in the first half of 2018 (revised data).

2.Retail indices
Retail price index
According to provisional data, in 2018 nominal prime retail prices increased on average by 4.3% relative to 2017 for the country as a whole, against an increase of 1.7% in 2017. Broken down by region, in 2018 nominal prime retail prices increased by 7.4% in Athens, 0.3% in Thessaloniki and 0.8% in the rest of Greece.
In the second half of 2018, nominal prime retail prices increased by 3.0% compared with the previous half-year, for the country as a whole (provisional data). The corresponding rates of change were 1.0% in the second half of 2017 and 2.3% in the first half of 2018 (revised data). According to regional data, in the second half of 2018, nominal prime retail prices increased by 4.9% in the greater Athens area, 1.3% in Thessaloniki and 0.4% in the rest of Greece, compared with the first half of 2018.
Retail rent index
In 2018, retail rents for the entire country declined on average by 0.5% in nominal terms (provisional data). The corresponding average annual rates of decline were 0.2% in Athens, 1.9% in Thessaloniki and 0.5% in the rest of Greece.
In the second half of 2018, retail rents for the country as a whole declined by 0.7% compared with the first half of 2018 (provisional data). In the second half of 2017, the respective rate of decline in rents was 0.3%, whereas in the first half of 2018 rents remained unchanged compared with the previous half-year (revised data).
Detailed tables on retail and office prices and rents by geographical area are published in the “Bulletin of Conjunctural Indicators” (Tables ΙΙ.9, ΙΙ.10, ΙΙ.11 and ΙΙ.12) and are also available on the Bank of Greece website under “Real Estate Market Analysis” section. 

Original source can be found here.

Source: Bank of Greece