The chief cashier of a bank must manage the cash holding so as to gain interest by investing excess cash where possible, but at the same time keep sufficient cash on hand to meet the banks needs. A major issue for the chief cashier is the uncertainty that results from the Federal Reserve Boards (the Feds) clearing balance. The clearing balance is the difference between the dollar value of checks written by the banks customers and cleared through the Fed, and the dollar value of checks received but written on other banks and clear through the Fed.

The chief cashier has recorded the last eight weeks of clearing balances (a longer period is available, but we will use just eight weeks here). The 40 observations of daily check clearings are shown below:

$21,697,208

-$32,977,193

$60,311,999

$29,981,227

$28,030,404

-$8,448,464

$53,479,593

$38,561,233

-$10,243,791

$30,056,844

$117,896,711

-$1,672,896

$24,650,044

$61,116,423

-$4,794,679

$24,066,627

$37,844,391

$81,001,561

$57,425,429

$28,157,292

$10,019,384

$21,886,686

$27,584,465

$8,059,567

-$3,648,650

$73,625,609

$34,537,810

$5,757,982

$40,873,515

$59,296,515

$29,387,165

-$31,816,724

$3,894,647

$5,027,402

$21,449,620

$31,467,912

$31,238,163

$23,307,164

$93,434,414

$65,555,653

How may use Excel to answer the following two questions:

Question 1. Provide point and interval estimates of the mean daily clearing balance.

Question 2. Provide point and interval predictions (or forecasts) of tomorrows clearing balance.