2021 - Sri Lanka - 20 Rupees
Census of Population and Housing
150th Anniversary

SPECIFICATIONS Denomination Rupees Twenty Alloy Nickel-plated Steel Diameter 28. mm Thickness 2.0 mm Weight 8.5 gms Shape Seven lobed Edge Plain Die-Axis 0° Issue 2,000,000? Mint CBPM, China.
	KM# 2??

Obverse : Logo of the Census of Population and Housing, with anniversary 150 above and years 1871-2021 below. ජන හා නිවාස සංගණනය in Sinhala above; குடிசன வீட்டுவசதிகள் தொகைமதிப்பு in Thamil on right; and CENSUS OF POPULATION AND HOUSING in English on left along the periphery.
Reverse : Huge numeral 20 with රුපියල් විස්සයි in Sinhala, இருபது ரூபாய் in Thamil and TWENTY RUPEES in English below. ශ්‍රී ලංකා in Sinhala above; இலங்கை in Thamil on left; and SRI LANKA in English on right along the periphery. The year of issue 2021 at the bottom.

The China Mint coins are issued neatly locked into two columns of a transparent plastic tray put within cellophane cover. The 100 coins, in pack weighed 890 grams on a digital scale. Printed in Blue on pack is

Commodity	150th Anniversary Census of Population and Housing
Pieces per packet	100

The mean weight of the coins is not mentioned in the Press Release, and just the thickness at 2 mm. The diameter is between 27.5 mm and 28.5 mm and listed as 28 mm.
Weighing each of the 100 coins on a digital pocket scale with a precision of 0.01 grams, I found that the coins weighed between 8.50 and 8.67 with a mean of 8.58 grams. The distribution had a rms dispersion of 0.035 (0.41% of mean weight). It had a positive skewness of 0.26 and was platykuratic with an negative excess kurtosis of -0.53. i.e. distribution flatter than normal.
Measurements of thickness of 50 coins tightly packed in tray was 102 mm giving thickness of 2.04mm indicating that they could be about 2% thicker than specified.
The Full range weights 2.0% of the average weight and corresponds to a difference in thickness of 0.04mm.
The coin is 1% thicker and 1% heavier than the first issued CBSL 70th anniversary commemorative coin.
Coin was scanned at 600 dpi, PhotoShoped and displayed at 254 dpi.

The first CPH in Ceylon was conducted in 1871 March 27th by the then Registrar General's Office. Since 1871, censuses were conducted, usually in every 10 years with certain exceptions. The population census taking was handed over to the Census department With its inception in early 1940s. In fact Ceylon/Sri Lanka has the longest history of Census takings among SAARC countries. The year 2021 marks its 150th Anniversary. The 15th CPH was originally planned to be conducted in 2021, concurrently with its anniversary. However, due to the COVID-19 pandemic 15th CPH has been postponed till 2022 - 2023.

The first coin was officially presented to the President of Sri Lanka Gotabaya Rajapaksa, by Mr. P M P Anura Kumara, Director General of DCS in the presence of by Ajith Nivard Cabraal, Governor of CBSL at the Presidential Secretariat on 2022 March 21st.

CBSL did not issue this coin at the CBSL museum and the CBSL cash counter was only open on Tuesdays for staff. Collectors had to wait to get them from a local bank when available. They were initially issued to state Banks BoC, PB, and NSB and now issued to any bank that requests them while stocks are available. Note only two million coins minted, less than the usual five million for a circulation commemorative As my movement were restricted by emergency surgery on the day of issue. I was able to pickup coins only on April 19th, 4 weeks after issue.