growth_rate_coronavirus.sql

USE `coronavirus`;
DROP procedure IF EXISTS `calculate_growth_rate`;

DELIMITER $$
USE `coronavirus`$$
CREATE DEFINER=`root`@`localhost` PROCEDURE `calculate_growth_rate`()
BEGIN


DECLARE last_case INT DEFAULT 0;
DECLARE first_case INT DEFAULT 0;

DECLARE most_recent_date date DEFAULT 0;
DECLARE first_day date DEFAULT 0;

DECLARE growth_rate float default 0.00;

set @last_case := (select cases from coronavirus.cases
order by id desc
limit 1);

set @first_case := (select cases from coronavirus.cases
order by id asc
limit 1);

set @most_recent_date := (select date from coronavirus.cases
order by id desc
limit 1);

set @first_day := (select date from coronavirus.cases
order by id asc
limit 1);


set @growth_rate := ((@last_case - @first_case) / @first_case * 100) / (select datediff(@most_recent_date, @first_day));

select @growth_rate as growth_rate;

END$$

DELIMITER ;

A stored procedure for determine growth rate
Formula is from here
https://pages.uoregon.edu/rgp/PPPM613/class8a.htm