Three Months Ended

March 31,

Year Ended December 31,

2018

2017

2016

2015

2014

2013

Consolidated net earnings

$

391,959

$

1,760,959

$

1,292,540

$

925,515

$

739,284

$

229,529

Add (Deduct):

Fixed charges

62,212

344,205

382,436

375,094

382,210

458,285

Capitalized interest

(11,119

)

(54,493

)

(64,815

)

(60,808

)

(61,457

)

(67,955

)

Earnings from unconsolidated

   entities, net

(62,656

)

(248,567

)

(206,307

)

(159,262

)

(134,288

)

(97,220

)

Distributed income from equity entities

85,229

307,220

286,651

284,664

294,890

68,319

Income tax expense (benefit)

16,552

54,609

54,564

23,090

(25,656

)

106,733

Earnings, as adjusted

$

482,177

$

2,163,933

$

1,745,069

$

1,388,293

$

1,194,983

$

697,691

Combined fixed charges and preferred stock

     dividends and unit distributions:

Interest expense

$

47,245

$

274,486

$

303,146

$

301,363

$

308,885

$

379,327

Capitalized interest

11,119

54,493

64,815

60,808

61,457

67,955

Portion of rents representative of the

   interest factor

3,848

15,226

14,475

12,923

11,868

11,003

Total fixed charges

62,212

344,205

382,436

375,094

382,210

458,285

Preferred stock dividends and unit

   distributions

1,476

6,499

6,714

6,651

7,431

18,391

Combined fixed charges and preferred

   stock dividends and unit distributions

$

63,688

$

350,704

$

389,150

$

381,745

$

389,641

$

476,676

Ratio of earnings, as adjusted, to combined

   fixed charges and preferred stock

        dividends and unit distributions

7.6

6.2

4.5

3.6

3.1

1.5