how many date of birts are if the previous club is chelsea
CREATE TABLE table_74223 (
    "No." real,
    "Name" text,
    "Place of Birth" text,
    "Date of Birth" text,
    "Previous Club" text,
    "Date Joined" text,
    "Fee" text,
    "Contract Expiry" text
)
SELECT COUNT("Date of Birth") FROM table_74223 WHERE "Previous Club" = 'Chelsea'
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: how many date of birts are if the previous club is chelsea ### Input: CREATE TABLE table_74223 (
    "No." real,
    "Name" text,
    "Place of Birth" text,
    "Date of Birth" text,
    "Previous Club" text,
    "Date Joined" text,
    "Fee" text,
    "Contract Expiry" text
) ### Response: SELECT COUNT("Date of Birth") FROM table_74223 WHERE "Previous Club" = 'Chelsea'