exponentialData = {
const rand = d3.randomNormal(0.1, 0.1);
const data = [{time: new Date(1989, 9, 19, 4, 30), value: 2}];
for (let i = 0; i < 1000; i++) {
const {time: t0, value: v0} = data.at(-1);
data.push({
time: d3.timeDay.offset(t0, 1),
value: v0 + (v0 * rand())
});
}
return data;
}